Organic electroluminescent materials and devices

Info

Patent number: 9929357
Type: Grant
Filed: Jul 22, 2014
Date of Patent: Mar 27, 2018
Patent Publication Number: 20160028023
Assignee: Universal Display Corporation (Ewing, NJ)
Inventors: Pierre-Luc T. Boudreault (Pennington, NJ), Harvey Wendt (Medford Lakes, NJ), Zeinab Elshenawy (Holland, PA), Chuanjun Xia (Lawrenceville, NJ)
Primary Examiner: Deepak R Rao
Application Number: 14/337,983

Abstract

A compound having a formula M(LA)x(LB)y(LC)z where ligand LA is ligand LB is and ligand LC is is disclosed. In the formula, M is a heavy metal, x and y are 1, or 2, and z is 0, 1, or 2, where x+y+z is the oxidation state of metal M. R1, R2, R3, and R4 are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl, and at least one of R1, R2, R3, and R4 has at least two C atoms. Rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring; at least one RB has the following structure and at least one of R6, R7, and R8 is alkyl, cycloalkyl, halide, and combinations thereof. Any adjacent substitutents of RA, RB, RC, and RD are optionally joined to form a ring.

Description

Description

PARTIES TO A JOINT RESEARCH AGREEMENT

The claimed invention was made by, on behalf of, and/or in connection with one or more of the following parties to a joint university corporation research agreement: Regents of the University of Michigan, Princeton University, University of Southern California, and the Universal Display Corporation. The agreement was in effect on and before the date the claimed invention was made, and the claimed invention was made as a result of activities undertaken within the scope of the agreement.

FIELD OF THE INVENTION

The present invention relates to compounds for use as emitters and devices, such as organic light emitting diodes, including the same.

BACKGROUND

Opto-electronic devices that make use of organic materials are becoming increasingly desirable for a number of reasons. Many of the materials used to make such devices are relatively inexpensive, so organic opto-electronic devices have the potential for cost advantages over inorganic devices. In addition, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications such as fabrication on a flexible substrate. Examples of organic opto-electronic devices include organic light emitting devices (OLEDs), organic phototransistors, organic photovoltaic cells, and organic photodetectors. For OLEDs, the organic materials may have performance advantages over conventional materials. For example, the wavelength at which an organic emissive layer emits light may generally be readily tuned with appropriate dopants.

OLEDs make use of thin organic films that emit light when voltage is applied across the device. OLEDs are becoming an increasingly interesting technology for use in applications such as flat panel displays, illumination, and backlighting. Several OLED materials and configurations are described in U.S. Pat. Nos. 5,844,363, 6,303,238, and 5,707,745, which are incorporated herein by reference in their entirety.

One application for phosphorescent emissive molecules is a full color display. Industry standards for such a display call for pixels adapted to emit particular colors, referred to as “saturated” colors. In particular, these standards call for saturated red, green, and blue pixels. Color may be measured using CIE coordinates, which are well known to the art.

One example of a green emissive molecule is tris(2-phenylpyridine) iridium, denoted Ir(ppy)₃, which has the following structure:

In this, and later figures herein, we depict the dative bond from nitrogen to metal (here, Ir) as a straight line.

As used herein, the term “organic” includes polymeric materials as well as small molecule organic materials that may be used to fabricate organic opto-electronic devices. “Small molecule” refers to any organic material that is not a polymer, and “small molecules” may actually be quite large. Small molecules may include repeat units in some circumstances. For example, using a long chain alkyl group as a substituent does not remove a molecule from the “small molecule” class. Small molecules may also be incorporated into polymers, for example as a pendent group on a polymer backbone or as a part of the backbone. Small molecules may also serve as the core moiety of a dendrimer, which consists of a series of chemical shells built on the core moiety. The core moiety of a dendrimer may be a fluorescent or phosphorescent small molecule emitter. A dendrimer may be a “small molecule,” and it is believed that all dendrimers currently used in the field of OLEDs are small molecules.

As used herein, “top” means furthest away from the substrate, while “bottom” means closest to the substrate. Where a first layer is described as “disposed over” a second layer, the first layer is disposed further away from substrate. There may be other layers between the first and second layer, unless it is specified that the first layer is “in contact with” the second layer. For example, a cathode may be described as “disposed over” an anode, even though there are various organic layers in between.

As used herein, “solution processable” means capable of being dissolved, dispersed, or transported in and/or deposited from a liquid medium, either in solution or suspension form.

A ligand may be referred to as “photoactive” when it is believed that the ligand directly contributes to the photoactive properties of an emissive material. A ligand may be referred to as “ancillary” when it is believed that the ligand does not contribute to the photoactive properties of an emissive material, although an ancillary ligand may alter the properties of a photoactive ligand.

As used herein, and as would be generally understood by one skilled in the art, a first “Highest Occupied Molecular Orbital” (HOMO) or “Lowest Unoccupied Molecular Orbital” (LUMO) energy level is “greater than” or “higher than” a second HOMO or LUMO energy level if the first energy level is closer to the vacuum energy level. Since ionization potentials (IP) are measured as a negative energy relative to a vacuum level, a higher HOMO energy level corresponds to an IP having a smaller absolute value (an IP that is less negative). Similarly, a higher LUMO energy level corresponds to an electron affinity (EA) having a smaller absolute value (an EA that is less negative). On a conventional energy level diagram, with the vacuum level at the top, the LUMO energy level of a material is higher than the HOMO energy level of the same material. A “higher” HOMO or LUMO energy level appears closer to the top of such a diagram than a “lower” HOMO or LUMO energy level.

As used herein, and as would be generally understood by one skilled in the art, a first work function is “greater than” or “higher than” a second work function if the first work function has a higher absolute value. Because work functions are generally measured as negative numbers relative to vacuum level, this means that a “higher” work function is more negative. On a conventional energy level diagram, with the vacuum level at the top, a “higher” work function is illustrated as further away from the vacuum level in the downward direction. Thus, the definitions of HOMO and LUMO energy levels follow a different convention than work functions.

More details on OLEDs, and the definitions described above, can be found in U.S. Pat. No. 7,279,704, which is incorporated herein by reference in its entirety.

SUMMARY OF THE INVENTION

According to an embodiment, a compound is provided that has a structure according to formula M(L_A)_x(L_B)_y(L_C)_z:

wherein the ligand L_Ais

wherein the ligand L_Bis

and

wherein the ligand L_Cis

In the compounds of formula M(L_A)_x(L_B)_y(L_C)_z:

M is a metal having an atomic number greater than 40;

x is 1, or 2;

y is 1, or 2;

z is 0, 1, or 2;

x+y+z is the oxidation state of the metal M;

R¹, R², R³, and R⁴are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

at least one of R¹, R², R³, and R⁴has at least two C atoms;

R⁵is selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

R_A, R_C, and R_Deach independently represent mono, di, tri, or tetra substitution, or no substitution;

R_Brepresents mono, di, tri, tetra, penta, or hexa substitution;

at least one R_Bhas the following structure:

each of R_A, R_B, R_C, and R_Dare independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

any adjacent substitutents of R_A, R_B, R_C, and R_Dare optionally joined to form a ring;

R⁶, R⁷, and R⁸are independently selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof; and

at least one of R⁶, R⁷, and R⁸is not hydrogen or deuterium.

According to another embodiment, a first device comprising a first organic light emitting device is also provided. The first organic light emitting device can include an anode, a cathode, and an organic layer, disposed between the anode and the cathode. The organic layer can include a compound of formula M(L_A)_x(L_B)_y(L_C)_z. The first device can be a consumer product, an organic light-emitting device, and/or a lighting panel.

Formulations containing a compound of formula M(L_A)_x(L_B)_y(L_C)_zare also provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an organic light emitting device.

FIG. 2 shows an inverted organic light emitting device that does not have a separate electron transport layer.

FIG. 3 shows the structure of the ligands of formula M(L_A)_x(L_B)_y(L_C)_zas disclosed herein.

DETAILED DESCRIPTION

Generally, an OLED comprises at least one organic layer disposed between and electrically connected to an anode and a cathode. When a current is applied, the anode injects holes and the cathode injects electrons into the organic layer(s). The injected holes and electrons each migrate toward the oppositely charged electrode. When an electron and hole localize on the same molecule, an “exciton,” which is a localized electron-hole pair having an excited energy state, is formed. Light is emitted when the exciton relaxes via a photoemissive mechanism. In some cases, the exciton may be localized on an excimer or an exciplex. Non-radiative mechanisms, such as thermal relaxation, may also occur, but are generally considered undesirable.

The initial OLEDs used emissive molecules that emitted light from their singlet states (“fluorescence”) as disclosed, for example, in U.S. Pat. No. 4,769,292, which is incorporated by reference in its entirety. Fluorescent emission generally occurs in a time frame of less than 10 nanoseconds.

More recently, OLEDs having emissive materials that emit light from triplet states (“phosphorescence”) have been demonstrated. Baldo et al., “Highly Efficient Phosphorescent Emission from Organic Electroluminescent Devices,” Nature, vol. 395, 151-154, 1998; (“Baldo-I”) and Baldo et al., “Very high-efficiency green organic light-emitting devices based on electrophosphorescence,” Appl. Phys. Lett., vol. 75, No. 3, 4-6 (1999) (“Baldo-II”), which are incorporated by reference in their entireties. Phosphorescence is described in more detail in U.S. Pat. No. 7,279,704 at cols. 5-6, which are incorporated by reference.

FIG. 1 shows an organic light emitting device 100. The figures are not necessarily drawn to scale. Device 100 may include a substrate 110, an anode 115, a hole injection layer 120, a hole transport layer 125, an electron blocking layer 130, an emissive layer 135, a hole blocking layer 140, an electron transport layer 145, an electron injection layer 150, a protective layer 155, a cathode 160, and a barrier layer 170. Cathode 160 is a compound cathode having a first conductive layer 162 and a second conductive layer 164. Device 100 may be fabricated by depositing the layers described, in order. The properties and functions of these various layers, as well as example materials, are described in more detail in U.S. Pat. No. 7,279,704 at cols. 6-10, which are incorporated by reference.

More examples for each of these layers are available. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. An example of a p-doped hole transport layer is m-MTDATA doped with F₄-TCNQ at a molar ratio of 50:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of emissive and host materials are disclosed in U.S. Pat. No. 6,303,238 to Thompson et al., which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. Patent Application Publication No. 2003/0230980, which is incorporated by reference in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entireties, disclose examples of cathodes including compound cathodes having a thin layer of metal such as Mg:Ag with an overlying transparent, electrically-conductive, sputter-deposited ITO layer. The theory and use of blocking layers is described in more detail in U.S. Pat. No. 6,097,147 and U.S. Patent Application Publication No. 2003/0230980, which are incorporated by reference in their entireties. Examples of injection layers are provided in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety. A description of protective layers may be found in U.S. Patent Application Publication No. 2004/0174116, which is incorporated by reference in its entirety.

FIG. 2 shows an inverted OLED 200. The device includes a substrate 210, a cathode 215, an emissive layer 220, a hole transport layer 225, and an anode 230. Device 200 may be fabricated by depositing the layers described, in order. Because the most common OLED configuration has a cathode disposed over the anode, and device 200 has cathode 215 disposed under anode 230, device 200 may be referred to as an “inverted” OLED. Materials similar to those described with respect to device 100 may be used in the corresponding layers of device 200. FIG. 2 provides one example of how some layers may be omitted from the structure of device 100.

The simple layered structure illustrated in FIGS. 1 and 2 is provided by way of non-limiting example, and it is understood that embodiments of the invention may be used in connection with a wide variety of other structures. The specific materials and structures described are exemplary in nature, and other materials and structures may be used. Functional OLEDs may be achieved by combining the various layers described in different ways, or layers may be omitted entirely, based on design, performance, and cost factors. Other layers not specifically described may also be included. Materials other than those specifically described may be used. Although many of the examples provided herein describe various layers as comprising a single material, it is understood that combinations of materials, such as a mixture of host and dopant, or more generally a mixture, may be used. Also, the layers may have various sublayers. The names given to the various layers herein are not intended to be strictly limiting. For example, in device 200, hole transport layer 225 transports holes and injects holes into emissive layer 220, and may be described as a hole transport layer or a hole injection layer. In one embodiment, an OLED may be described as having an “organic layer” disposed between a cathode and an anode. This organic layer may comprise a single layer, or may further comprise multiple layers of different organic materials as described, for example, with respect to FIGS. 1 and 2.

Structures and materials not specifically described may also be used, such as OLEDs comprised of polymeric materials (PLEDs) such as disclosed in U.S. Pat. No. 5,247,190 to Friend et al., which is incorporated by reference in its entirety. By way of further example, OLEDs having a single organic layer may be used. OLEDs may be stacked, for example as described in U.S. Pat. No. 5,707,745 to Forrest et al, which is incorporated by reference in its entirety. The OLED structure may deviate from the simple layered structure illustrated in FIGS. 1 and 2. For example, the substrate may include an angled reflective surface to improve out-coupling, such as a mesa structure as described in U.S. Pat. No. 6,091,195 to Forrest et al., and/or a pit structure as described in U.S. Pat. No. 5,834,893 to Bulovic et al., which are incorporated by reference in their entireties.

Unless otherwise specified, any of the layers of the various embodiments may be deposited by any suitable method. For the organic layers, preferred methods include thermal evaporation, ink-jet, such as described in U.S. Pat. Nos. 6,013,982 and 6,087,196, which are incorporated by reference in their entireties, organic vapor phase deposition (OVPD), such as described in U.S. Pat. No. 6,337,102 to Forrest et al., which is incorporated by reference in its entirety, and deposition by organic vapor jet printing (OVJP), such as described in U.S. Pat. No. 7,431,968, which is incorporated by reference in its entirety. Other suitable deposition methods include spin coating and other solution based processes. Solution based processes are preferably carried out in nitrogen or an inert atmosphere. For the other layers, preferred methods include thermal evaporation. Preferred patterning methods include deposition through a mask, cold welding such as described in U.S. Pat. Nos. 6,294,398 and 6,468,819, which are incorporated by reference in their entireties, and patterning associated with some of the deposition methods such as ink-jet and OVJD. Other methods may also be used. The materials to be deposited may be modified to make them compatible with a particular deposition method. For example, substituents such as alkyl and aryl groups, branched or unbranched, and preferably containing at least 3 carbons, may be used in small molecules to enhance their ability to undergo solution processing. Substituents having 20 carbons or more may be used, and 3-20 carbons is a preferred range. Materials with asymmetric structures may have better solution processability than those having symmetric structures, because asymmetric materials may have a lower tendency to recrystallize. Dendrimer substituents may be used to enhance the ability of small molecules to undergo solution processing.

Devices fabricated in accordance with embodiments of the present invention may further optionally comprise a barrier layer. One purpose of the barrier layer is to protect the electrodes and organic layers from damaging exposure to harmful species in the environment including moisture, vapor and/or gases, etc. The barrier layer may be deposited over, under or next to a substrate, an electrode, or over any other parts of a device including an edge. The barrier layer may comprise a single layer, or multiple layers. The barrier layer may be formed by various known chemical vapor deposition techniques and may include compositions having a single phase as well as compositions having multiple phases. Any suitable material or combination of materials may be used for the barrier layer. The barrier layer may incorporate an inorganic or an organic compound or both. The preferred barrier layer comprises a mixture of a polymeric material and a non-polymeric material as described in U.S. Pat. No. 7,968,146, PCT Pat. Application Nos. PCT/US2007/023098 and PCT/US2009/042829, which are herein incorporated by reference in their entireties. To be considered a “mixture”, the aforesaid polymeric and non-polymeric materials comprising the barrier layer should be deposited under the same reaction conditions and/or at the same time. The weight ratio of polymeric to non-polymeric material may be in the range of 95:5 to 5:95. The polymeric material and the non-polymeric material may be created from the same precursor material. In one example, the mixture of a polymeric material and a non-polymeric material consists essentially of polymeric silicon and inorganic silicon.

Devices fabricated in accordance with embodiments of the invention may be incorporated into a wide variety of consumer products, including flat panel displays, computer monitors, medical monitors, televisions, billboards, lights for interior or exterior illumination and/or signaling, heads up displays, fully transparent displays, flexible displays, laser printers, telephones, cell phones, personal digital assistants (PDAs), laptop computers, digital cameras, camcorders, viewfinders, micro-displays, 3-D displays, vehicles, a large area wall, theater or stadium screen, or a sign. Various control mechanisms may be used to control devices fabricated in accordance with the present invention, including passive matrix and active matrix. Many of the devices are intended for use in a temperature range comfortable to humans, such as 18 degrees C. to 30 degrees C., and more preferably at room temperature (20-25 degrees C.), but could be used outside this temperature range, for example, from −40 degree C. to +80 degree C.

The materials and structures described herein may have applications in devices other than OLEDs. For example, other optoelectronic devices such as organic solar cells and organic photodetectors may employ the materials and structures. More generally, organic devices, such as organic transistors, may employ the materials and structures.

The term “halo” or “halogen” as used herein includes fluorine, chlorine, bromine, and iodine.

The term “alkyl” as used herein contemplates both straight and branched chain alkyl radicals. Preferred alkyl groups are those containing from one to fifteen carbon atoms and includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, and the like. Additionally, the alkyl group may be optionally substituted.

The term “cycloalkyl” as used herein contemplates cyclic alkyl radicals. Preferred cycloalkyl groups are those containing 3 to 7 carbon atoms and includes cyclopropyl, cyclopentyl, cyclohexyl, and the like. Additionally, the cycloalkyl group may be optionally substituted.

The term “alkenyl” as used herein contemplates both straight and branched chain alkene radicals. Preferred alkenyl groups are those containing two to fifteen carbon atoms. Additionally, the alkenyl group may be optionally substituted.

The term “alkynyl” as used herein contemplates both straight and branched chain alkyne radicals. Preferred alkynyl groups are those containing two to fifteen carbon atoms. Additionally, the alkynyl group may be optionally substituted.

The terms “aralkyl” or “arylalkyl” as used herein are used interchangeably and contemplate an alkyl group that has as a substituent an aromatic group. Additionally, the aralkyl group may be optionally substituted.

The term “heterocyclic group” as used herein contemplates aromatic and non-aromatic cyclic radicals. Hetero-aromatic cyclic radicals also means heteroaryl. Preferred hetero-non-aromatic cyclic groups are those containing 3 or 7 ring atoms which includes at least one hetero atom, and includes cyclic amines such as morpholino, piperdino, pyrrolidino, and the like, and cyclic ethers, such as tetrahydrofuran, tetrahydropyran, and the like. Additionally, the heterocyclic group may be optionally substituted.

The term “aryl” or “aromatic group” as used herein contemplates single-ring groups and polycyclic ring systems. The polycyclic rings may have two or more rings in which two carbons are common to two adjoining rings (the rings are “fused”) wherein at least one of the rings is aromatic, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Additionally, the aryl group may be optionally substituted.

The term “heteroaryl” as used herein contemplates single-ring hetero-aromatic groups that may include from one to three heteroatoms, for example, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, triazole, pyrazole, pyridine, pyrazine and pyrimidine, and the like. The term heteroaryl also includes polycyclic hetero-aromatic systems having two or more rings in which two atoms are common to two adjoining rings (the rings are “fused”) wherein at least one of the rings is a heteroaryl, e.g., the other rings can be cycloalkyls, cycloalkenyls, aryl, heterocycles, and/or heteroaryls. Additionally, the heteroaryl group may be optionally substituted.

The alkyl, cycloalkyl, alkenyl, alkynyl, aralkyl, heterocyclic group, aryl, and heteroaryl may be optionally substituted with one or more substituents selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, cyclic amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

As used herein, “substituted” indicates that a substituent other than H is bonded to the relevant position, such as carbon. Thus, for example, where R¹is mono-substituted, then one R¹must be other than H. Similarly, where R¹is di-substituted, then two of R¹must be other than H. Similarly, where R¹is unsubstituted, R¹is hydrogen for all available positions.

The “aza” designation in the fragments described herein, i.e. aza-dibenzofuran, aza-dibenzothiophene, etc. means that one or more of the C—H groups in the respective fragment can be replaced by a nitrogen atom, for example, and without any limitation, azatriphenylene encompasses both dibenzo[f,h]quinoxaline and dibenzo[f,h]quinoline. One of ordinary skill in the art can readily envision other nitrogen analogs of the aza-derivatives described above, and all such analogs are intended to be encompassed by the terms as set forth herein.

It is to be understood that when a molecular fragment is described as being a substituent or otherwise attached to another moiety, its name may be written as if it were a fragment (e.g. phenyl, phenylene, naphthyl, dibenzofuryl) or as if it were the whole molecule (e.g. benzene, naphthalene, dibenzofuran). As used herein, these different ways of designating a substituent or attached fragment are considered to be equivalent.

According to one embodiment, a compound having a structure according to formula M(L_A)_x(L_B)_y(L_C)_z:

wherein the ligand L_Ais

wherein the ligand L_Bis

and

wherein the ligand L_Cis

is disclosed.
In the compound of formula M(L_A)_x(L_B)_y(L_C)_z:

M is a metal having an atomic number greater than 40;

x is 1, or 2;

y is 1, or 2;

z is 0, 1, or 2;

x+y+z is the oxidation state of the metal M;

R¹, R², R³, and R⁴are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

at least one of R¹, R², R³, and R⁴has at least two C atoms;

R⁵is selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

rings A, C, and D are each independently a 5 or 6-membered carbocyclic or heterocyclic ring;

R_A, R_C, and R_Deach independently represent mono, di, tri, or tetra substitution, or no substitution;

R_Brepresents mono, di, tri, tetra, penta, or hexa substitution;

at least one R_Bhas the following structure:

each of R_A, R_B, R_C, and R_Dare independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

any adjacent substitutents of R_A, R_B, R_C, and R_Dare optionally joined to form a ring;

R⁶, R⁷, and R⁸are independently selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof; and

at least one of R⁶, R⁷, and R⁸is not hydrogen or deuterium.

In some embodiments, both R⁶& R⁸are alkyl. In some embodiments, R⁶& R⁸are the same and are both alkyl. In some embodiments, at least one of R⁶, R⁷, and R⁸comprises at least 2 C atoms. In some embodiments, at least one of R⁶, R⁷, and R⁸comprises at least 3 C atoms, while at least one of R⁶, R⁷, and R⁸comprises at least 4 C atoms in other embodiments.

In some embodiments, R_Bis mono substituted. In some embodiments, R_Bis at least disubstituted.

In some embodiments, M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu. In some embodiments, M is Ir.

In some embodiments, ring A is benzene. In some embodiments, ring C is benzene and ring D is pyridine.

In some embodiments, R⁵is selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof. In some embodiments, R⁵is hydrogen.

In some embodiments, R¹, R², R³, and R⁴are alkyl or cycloalkyl. In some such embodiments, R¹, R², R³, and R⁴are independently selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully deuterated variants thereof, and combinations thereof. In some embodiments, R⁶, R⁷, and R⁸are independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully fluorinated variants thereof, fluorine, and combinations thereof.

In some embodiments, the compound has the structure of formula 1:

In some embodiments of formula 1, n is 1 or 2. In some embodiments of formula 1, n is 2.

In some embodiments, R_Ais selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof.

In some embodiments, the compound has the structure of formula 2:

In some embodiments of formula 2. R⁹, and R¹⁰are independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof.

In some embodiments, ligand L_Ais selected from the group consisting of L_A1to L_A104listed below:

L_A1through L_A13, each represented by the formula

wherein in L_A1: R⁷═CH₃, and R⁶═R⁸═H,
in L_A2: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A3: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A4: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A5: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A6: R⁷═F, and R⁶═R⁸═H,
in L_A7: R⁷═H, and R⁶═R⁸═CH₃,
in L_A8: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A9: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A10: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A11: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A12: R⁷═H, and R⁶═R⁸═F, and
in L_A13: R⁶═R⁷═R⁸═CH₃,
L_A14through L_A26, each represented by the formula

wherein in L_A14: R⁷═CH₃, and R⁶═R⁸═H,
in L_A15: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A16: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A17: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A18: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A19: R⁷═F, and R⁶═R⁸═H,
in L_A20: R⁷═H, and R⁶═R⁸═CH₃,
in L_A21: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A22: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A23: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A24: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A25: R⁷═H, and R⁶═R⁸═F, and
in L_A26: R⁶═R⁷═R⁸═CH₃,
L_A27through L_A39, each represented by the formula

wherein in L_A27: R⁷═CH₃, and R⁶═R⁸═H,
in L_A28: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A29: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A30: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A31: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A32: R⁷═F, and R⁶═R⁸═H,
in L_A33: R⁷═H, and R⁶═R⁸═CH₃,
in L_A34: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A35: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A36: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A37: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A38: R⁷═H, and R⁶═R⁸═F, and
in L_A39: R⁶═R⁷═R⁸═CH₃,
L_A40through L_A52, each represented by the formula

wherein in L_A40: R⁷═CH₃, and R⁶═R⁸═H,
in L_A41: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A42: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A43: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A44: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A45: R⁷═F, and R⁶═R⁸═H,
in L_A46: R⁷═H, and R⁶═R⁸═CH₃,
in L_A47: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A48: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A49: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A50: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A51: R⁷═H, and R⁶═R⁸═F, and
in L_A52: R⁶═R⁷═R⁸═CH₃,
L_A53through L_A65, each represented by the formula

wherein in L_A53: R⁷═CH₃, and R⁶═R⁸═H,
in L_A54: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A55: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A56: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A57: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A58: R⁷═F, and R⁶═R⁸═H,
in L_A59: R⁷═H, and R⁶═R⁸═CH₃,
in L_A60: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A61: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A62: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A63: R⁷═H, and R⁶═R⁸=neopenty,
in L_A64: R⁷═H, and R⁶═R⁸═F, and
in L_A65: R⁶═R⁷═R⁸═CH₃,
L_A66through L_A78, each represented by the formula

wherein in L_A66: R⁷═CH₃, and R⁶═R⁸═H,
in L_A67: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A68: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A69: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A70: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A71: R⁷═F, and R⁶═R⁸═H,
in L_A72: R⁷═H, and R⁶═R⁸═CH₃,
in L_A73: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A74: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A75: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A76: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A77: R⁷═H, and R⁶═R⁸═F, and
in L_A78: R⁶═R⁷═R⁸═CH₃,
L_A79through L_A91, each represented by the formula

wherein in L_A79: R⁷═CH₃, and R⁶═R⁸═H,
in L_A80: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A81: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A82: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A83: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A84: R⁷═F, and R⁶═R⁸═H,
in L_A85: R⁷═H, and R⁶═R⁸═CH₃,
in L_A86: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A87: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A88: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A89: R⁷═H, and R⁶═R⁸neopentyl,
in L_A90: R⁷═H, and R⁶═R⁸═F, and
in L_A91: R⁶═R⁷═R⁸═CH₃, and
L_A92through L_A104, each represented by the formula

wherein in L_A92: R⁷═CH₃, and R⁶═R⁸═H,
in L_A93: R⁷=isopropyl, and R⁶═R⁸═H,
in L_A94: R⁷=isobutyl, and R⁶═R⁸═H,
in L_A95: R⁷=cyclopentyl, and R⁶═R⁸═H,
in L_A96: R⁷=neopentyl, and R⁶═R⁸═H,
in L_A97: R⁷═F, and R⁶═R⁸═H,
in L_A98: R⁷═H, and R⁶═R⁸═CH₃,
in L_A99: R⁷═H, and R⁶═R⁸=isopropyl,
in L_A100: R⁷═H, and R⁶═R⁸=isobutyl,
in L_A101: R⁷═H, and R⁶═R⁸=cyclopentyl,
in L_A102: R⁷═H, and R⁶═R⁸=neopentyl,
in L_A103: R⁷═H, and R⁶═R⁸═F, and
in L_A104: R⁶═R⁷═R⁸═CH₃.

In some embodiments, ligand L_Bis selected from the group consisting of L_B1-L_B9listed below:

In some embodiments, the compound comprises ligand L_Aand ligand L_Bselected from the group consisting of:

Compound Number L_A L_B 1 L_A1 L_B1 2 L_A2 L_B1 3 L_A3 L_B1 4 L_A4 L_B1 5 L_A5 L_B1 6 L_A6 L_B1 7 L_A7 L_B1 8 L_A8 L_B1 9 L_A9 L_B1 10 L_A10 L_B1 11 L_A11 L_B1 12 L_A12 L_B1 13 L_A13 L_B1 14 L_A14 L_B1 15 L_A15 L_B1 16 L_A16 L_B1 17 L_A17 L_B1 18 L_A18 L_B1 19 L_A19 L_B1 20 L_A20 L_B1 21 L_A21 L_B1 22 L_A22 L_B1 23 L_A23 L_B1 24 L_A24 L_B1 25 L_A25 L_B1 26 L_A26 L_B1 27 L_A27 L_B1 28 L_A28 L_B1 29 L_A29 L_B1 30 L_A30 L_B1 31 L_A31 L_B1 32 L_A32 L_B1 33 L_A33 L_B1 34 L_A34 L_B1 35 L_A35 L_B1 36 L_A36 L_B1 37 L_A37 L_B1 38 L_A38 L_B1 39 L_A39 L_B1 40 L_A40 L_B1 41 L_A41 L_B1 42 L_A42 L_B1 43 L_A43 L_B1 44 L_A44 L_B1 45 L_A45 L_B1 46 L_A46 L_B1 47 L_A47 L_B1 48 L_A48 L_B1 49 L_A49 L_B1 50 L_A50 L_B1 51 L_A51 L_B1 52 L_A52 L_B1 53 L_A53 L_B1 54 L_A54 L_B1 55 L_A55 L_B1 56 L_A56 L_B1 57 L_A57 L_B1 58 L_A58 L_B1 59 L_A59 L_B1 60 L_A60 L_B1 61 L_A61 L_B1 62 L_A62 L_B1 63 L_A63 L_B1 64 L_A64 L_B1 65 L_A65 L_B1 66 L_A66 L_B1 67 L_A67 L_B1 68 L_A68 L_B1 69 L_A69 L_B1 70 L_A70 L_B1 71 L_A71 L_B1 72 L_A72 L_B1 73 L_A73 L_B1 74 L_A74 L_B1 75 L_A75 L_B1 76 L_A76 L_B1 77 L_A77 L_B1 78 L_A78 L_B1 79 L_A79 L_B1 80 L_A80 L_B1 81 L_A81 L_B1 82 L_A82 L_B1 83 L_A83 L_B1 84 L_A84 L_B1 85 L_A85 L_B1 86 L_A86 L_B1 87 L_A87 L_B1 88 L_A88 L_B1 89 L_A89 L_B1 90 L_A90 L_B1 91 L_A91 L_B1 92 L_A92 L_B1 93 L_A93 L_B1 94 L_A94 L_B1 95 L_A95 L_B1 96 L_A96 L_B1 97 L_A97 L_B1 98 L_A98 L_B1 99 L_A99 L_B1 100 L_A100 L_B1 101 L_A101 L_B1 102 L_A102 L_B1 103 L_A103 L_B1 104 L_A104 L_B1 105 L_A1 L_B2 106 L_A2 L_B2 107 L_A3 L_B2 108 L_A4 L_B2 109 L_A5 L_B2 110 L_A6 L_B2 111 L_A7 L_B2 112 L_A8 L_B2 113 L_A9 L_B2 114 L_A10 L_B2 115 L_A11 L_B2 116 L_A12 L_B2 117 L_A13 L_B2 118 L_A14 L_B2 119 L_A15 L_B2 120 L_A16 L_B2 121 L_A17 L_B2 122 L_A18 L_B2 123 L_A19 L_B2 124 L_A20 L_B2 125 L_A21 L_B2 126 L_A22 L_B2 127 L_A23 L_B2 128 L_A24 L_B2 129 L_A25 L_B2 130 L_A26 L_B2 131 L_A27 L_B2 132 L_A28 L_B2 133 L_A29 L_B2 134 L_A30 L_B2 135 L_A31 L_B2 136 L_A32 L_B2 137 L_A33 L_B2 138 L_A34 L_B2 139 L_A35 L_B2 140 L_A36 L_B2 141 L_A37 L_B2 142 L_A38 L_B2 143 L_A39 L_B2 144 L_A40 L_B2 145 L_A41 L_B2 146 L_A42 L_B2 147 L_A43 L_B2 148 L_A44 L_B2 149 L_A45 L_B2 150 L_A46 L_B2 151 L_A47 L_B2 152 L_A48 L_B2 153 L_A49 L_B2 154 L_A50 L_B2 155 L_A51 L_B2 156 L_A52 L_B2 157 L_A53 L_B2 158 L_A54 L_B2 159 L_A55 L_B2 160 L_A56 L_B2 161 L_A57 L_B2 162 L_A58 L_B2 163 L_A59 L_B2 164 L_A60 L_B2 165 L_A61 L_B2 166 L_A62 L_B2 167 L_A63 L_B2 168 L_A64 L_B2 169 L_A65 L_B2 170 L_A66 L_B2 171 L_A67 L_B2 172 L_A68 L_B2 173 L_A69 L_B2 174 L_A70 L_B2 175 L_A71 L_B2 176 L_A72 L_B2 177 L_A73 L_B2 178 L_A74 L_B2 179 L_A75 L_B2 180 L_A76 L_B2 181 L_A77 L_B2 182 L_A78 L_B2 183 L_A79 L_B2 184 L_A80 L_B2 185 L_A81 L_B2 186 L_A82 L_B2 187 L_A83 L_B2 188 L_A84 L_B2 189 L_A85 L_B2 190 L_A86 L_B2 191 L_A87 L_B2 192 L_A88 L_B2 193 L_A89 L_B2 194 L_A90 L_B2 195 L_A91 L_B2 196 L_A92 L_B2 197 L_A93 L_B2 198 L_A94 L_B2 199 L_A95 L_B2 200 L_A96 L_B2 201 L_A97 L_B2 202 L_A98 L_B2 203 L_A99 L_B2 204 L_A100 L_B2 205 L_A101 L_B2 206 L_A102 L_B2 207 L_A103 L_B2 208 L_A104 L_B2 209 L_A1 L_B3 210 L_A2 L_B3 211 L_A3 L_B3 212 L_A4 L_B3 213 L_A5 L_B3 214 L_A6 L_B3 215 L_A7 L_B3 216 L_A8 L_B3 217 L_A9 L_B3 218 L_A10 L_B3 219 L_A11 L_B3 220 L_A12 L_B3 221 L_A13 L_B3 222 L_A14 L_B3 223 L_A15 L_B3 224 L_A16 L_B3 225 L_A17 L_B3 226 L_A18 L_B3 227 L_A19 L_B3 228 L_A20 L_B3 229 L_A21 L_B3 230 L_A22 L_B3 231 L_A23 L_B3 232 L_A24 L_B3 233 L_A25 L_B3 234 L_A26 L_B3 235 L_A27 L_B3 236 L_A28 L_B3 237 L_A29 L_B3 238 L_A30 L_B3 239 L_A31 L_B3 240 L_A32 L_B3 241 L_A33 L_B3 242 L_A34 L_B3 243 L_A35 L_B3 244 L_A36 L_B3 245 L_A37 L_B3 246 L_A38 L_B3 247 L_A39 L_B3 248 L_A40 L_B3 249 L_A41 L_B3 250 L_A42 L_B3 251 L_A43 L_B3 252 L_A44 L_B3 253 L_A45 L_B3 254 L_A46 L_B3 255 L_A47 L_B3 256 L_A48 L_B3 257 L_A49 L_B3 258 L_A50 L_B3 259 L_A51 L_B3 260 L_A52 L_B3 261 L_A53 L_B3 262 L_A54 L_B3 263 L_A55 L_B3 264 L_A56 L_B3 265 L_A57 L_B3 266 L_A58 L_B3 267 L_A59 L_B3 268 L_A60 L_B3 269 L_A61 L_B3 270 L_A62 L_B3 271 L_A63 L_B3 272 L_A64 L_B3 273 L_A65 L_B3 274 L_A66 L_B3 275 L_A67 L_B3 276 L_A68 L_B3 277 L_A69 L_B3 278 L_A70 L_B3 279 L_A71 L_B3 280 L_A72 L_B3 281 L_A73 L_B3 282 L_A74 L_B3 283 L_A75 L_B3 284 L_A76 L_B3 285 L_A77 L_B3 286 L_A78 L_B3 287 L_A79 L_B3 288 L_A80 L_B3 289 L_A81 L_B3 290 L_A82 L_B3 291 L_A83 L_B3 292 L_A84 L_B3 293 L_A85 L_B3 294 L_A86 L_B3 295 L_A87 L_B3 296 L_A88 L_B3 297 L_A89 L_B3 298 L_A90 L_B3 299 L_A91 L_B3 300 L_A92 L_B3 301 L_A93 L_B3 302 L_A94 L_B3 303 L_A95 L_B3 304 L_A96 L_B3 305 L_A97 L_B3 306 L_A98 L_B3 307 L_A99 L_B3 308 L_A100 L_B3 309 L_A101 L_B3 310 L_A102 L_B3 311 L_A103 L_B3 312 L_A104 L_B3 313 L_A1 L_B4 314 L_A2 L_B4 315 L_A3 L_B4 316 L_A4 L_B4 317 L_A5 L_B4 318 L_A6 L_B4 319 L_A7 L_B4 320 L_A8 L_B4 321 L_A9 L_B4 322 L_A10 L_B4 323 L_A11 L_B4 324 L_A12 L_B4 325 L_A13 L_B4 326 L_A14 L_B4 327 L_A15 L_B4 328 L_A16 L_B4 329 L_A17 L_B4 330 L_A18 L_B4 331 L_A19 L_B4 332 L_A20 L_B4 333 L_A21 L_B4 334 L_A22 L_B4 335 L_A23 L_B4 336 L_A24 L_B4 337 L_A25 L_B4 338 L_A26 L_B4 339 L_A27 L_B4 340 L_A28 L_B4 341 L_A29 L_B4 342 L_A30 L_B4 343 L_A31 L_B4 344 L_A32 L_B4 345 L_A33 L_B4 346 L_A34 L_B4 347 L_A35 L_B4 348 L_A36 L_B4 349 L_A37 L_B4 350 L_A38 L_B4 351 L_A39 L_B4 352 L_A40 L_B4 353 L_A41 L_B4 354 L_A42 L_B4 355 L_A43 L_B4 356 L_A44 L_B4 357 L_A45 L_B4 358 L_A46 L_B4 359 L_A47 L_B4 360 L_A48 L_B4 361 L_A49 L_B4 362 L_A50 L_B4 363 L_A51 L_B4 364 L_A52 L_B4 365 L_A53 L_B4 366 L_A54 L_B4 367 L_A55 L_B4 368 L_A56 L_B4 369 L_A57 L_B4 370 L_A58 L_B4 371 L_A59 L_B4 372 L_A60 L_B4 373 L_A61 L_B4 374 L_A62 L_B4 375 L_A63 L_B4 376 L_A64 L_B4 377 L_A65 L_B4 378 L_A66 L_B4 379 L_A67 L_B4 380 L_A68 L_B4 381 L_A69 L_B4 382 L_A70 L_B4 383 L_A71 L_B4 384 L_A72 L_B4 385 L_A73 L_B4 386 L_A74 L_B4 387 L_A75 L_B4 388 L_A76 L_B4 389 L_A77 L_B4 390 L_A78 L_B4 391 L_A79 L_B4 392 L_A80 L_B4 393 L_A81 L_B4 394 L_A82 L_B4 395 L_A83 L_B4 396 L_A84 L_B4 397 L_A85 L_B4 398 L_A86 L_B4 399 L_A87 L_B4 400 L_A88 L_B4 401 L_A89 L_B4 402 L_A90 L_B4 403 L_A91 L_B4 404 L_A92 L_B4 405 L_A93 L_B4 406 L_A94 L_B4 407 L_A95 L_B4 408 L_A96 L_B4 409 L_A97 L_B4 410 L_A98 L_B4 411 L_A99 L_B4 412 L_A100 L_B4 413 L_A101 L_B4 414 L_A102 L_B4 415 L_A103 L_B4 416 L_A104 L_B4 417 L_A1 L_B5 418 L_A2 L_B5 419 L_A3 L_B5 420 L_A4 L_B5 421 L_A5 L_B5 422 L_A6 L_B5 423 L_A7 L_B5 424 L_A8 L_B5 425 L_A9 L_B5 426 L_A10 L_B5 427 L_A11 L_B5 428 L_A12 L_B5 429 L_A13 L_B5 430 L_A14 L_B5 431 L_A15 L_B5 432 L_A16 L_B5 433 L_A17 L_B5 434 L_A18 L_B5 435 L_A19 L_B5 436 L_A20 L_B5 437 L_A21 L_B5 438 L_A22 L_B5 439 L_A23 L_B5 440 L_A24 L_B5 441 L_A25 L_B5 442 L_A26 L_B5 443 L_A27 L_B5 444 L_A28 L_B5 445 L_A29 L_B5 446 L_A30 L_B5 447 L_A31 L_B5 448 L_A32 L_B5 449 L_A33 L_B5 450 L_A34 L_B5 451 L_A35 L_B5 452 L_A36 L_B5 453 L_A37 L_B5 454 L_A38 L_B5 455 L_A39 L_B5 456 L_A40 L_B5 457 L_A41 L_B5 458 L_A42 L_B5 459 L_A43 L_B5 460 L_A44 L_B5 461 L_A45 L_B5 462 L_A46 L_B5 463 L_A47 L_B5 464 L_A48 L_B5 465 L_A49 L_B5 466 L_A50 L_B5 467 L_A51 L_B5 468 L_A52 L_B5 469 L_A53 L_B5 470 L_A54 L_B5 471 L_A55 L_B5 472 L_A56 L_B5 473 L_A57 L_B5 474 L_A58 L_B5 475 L_A59 L_B5 476 L_A60 L_B5 477 L_A61 L_B5 478 L_A62 L_B5 479 L_A63 L_B5 480 L_A64 L_B5 481 L_A65 L_B5 482 L_A66 L_B5 483 L_A67 L_B5 484 L_A68 L_B5 485 L_A69 L_B5 486 L_A70 L_B5 487 L_A71 L_B5 488 L_A72 L_B5 489 L_A73 L_B5 490 L_A74 L_B5 491 L_A75 L_B5 492 L_A76 L_B5 493 L_A77 L_B5 494 L_A78 L_B5 495 L_A79 L_B5 496 L_A80 L_B5 497 L_A81 L_B5 498 L_A82 L_B5 499 L_A83 L_B5 500 L_A84 L_B5 501 L_A85 L_B5 502 L_A86 L_B5 503 L_A87 L_B5 504 L_A88 L_B5 505 L_A89 L_B5 506 L_A90 L_B5 507 L_A91 L_B5 508 L_A92 L_B5 509 L_A93 L_B5 510 L_A94 L_B5 511 L_A95 L_B5 512 L_A96 L_B5 513 L_A97 L_B5 514 L_A98 L_B5 515 L_A99 L_B5 516 L_A100 L_B5 517 L_A101 L_B5 518 L_A102 L_B5 519 L_A103 L_B5 520 L_A104 L_B5 521 L_A1 L_B6 522 L_A2 L_B6 523 L_A3 L_B6 524 L_A4 L_B6 525 L_A5 L_B6 526 L_A6 L_B6 527 L_A7 L_B6 528 L_A8 L_B6 529 L_A9 L_B6 530 L_A10 L_B6 531 L_A11 L_B6 532 L_A12 L_B6 533 L_A13 L_B6 534 L_A14 L_B6 535 L_A15 L_B6 536 L_A16 L_B6 537 L_A17 L_B6 538 L_A18 L_B6 539 L_A19 L_B6 540 L_A20 L_B6 541 L_A21 L_B6 542 L_A22 L_B6 543 L_A23 L_B6 544 L_A24 L_B6 545 L_A25 L_B6 546 L_A26 L_B6 547 L_A27 L_B6 548 L_A28 L_B6 549 L_A29 L_B6 550 L_A30 L_B6 551 L_A31 L_B6 552 L_A32 L_B6 553 L_A33 L_B6 554 L_A34 L_B6 555 L_A35 L_B6 556 L_A36 L_B6 557 L_A37 L_B6 558 L_A38 L_B6 559 L_A39 L_B6 560 L_A40 L_B6 561 L_A41 L_B6 562 L_A42 L_B6 563 L_A43 L_B6 564 L_A44 L_B6 565 L_A45 L_B6 566 L_A46 L_B6 567 L_A47 L_B6 568 L_A48 L_B6 569 L_A49 L_B6 570 L_A50 L_B6 571 L_A51 L_B6 572 L_A52 L_B6 573 L_A53 L_B6 574 L_A54 L_B6 575 L_A55 L_B6 576 L_A56 L_B6 577 L_A57 L_B6 578 L_A58 L_B6 579 L_A59 L_B6 580 L_A60 L_B6 581 L_A61 L_B6 582 L_A62 L_B6 583 L_A63 L_B6 584 L_A64 L_B6 585 L_A65 L_B6 586 L_A66 L_B6 587 L_A67 L_B6 588 L_A68 L_B6 589 L_A69 L_B6 590 L_A70 L_B6 591 L_A71 L_B6 592 L_A72 L_B6 593 L_A73 L_B6 594 L_A74 L_B6 595 L_A75 L_B6 596 L_A76 L_B6 597 L_A77 L_B6 598 L_A78 L_B6 599 L_A79 L_B6 600 L_A80 L_B6 601 L_A81 L_B6 602 L_A82 L_B6 603 L_A83 L_B6 604 L_A84 L_B6 605 L_A85 L_B6 606 L_A86 L_B6 607 L_A87 L_B6 608 L_A88 L_B6 609 L_A89 L_B6 610 L_A90 L_B6 611 L_A91 L_B6 612 L_A92 L_B6 613 L_A93 L_B6 614 L_A94 L_B6 615 L_A95 L_B6 616 L_A96 L_B6 617 L_A97 L_B6 618 L_A98 L_B6 619 L_A99 L_B6 620 L_A100 L_B6 621 L_A101 L_B6 622 L_A102 L_B6 623 L_A103 L_B6 624 L_A104 L_B6 625 L_A1 L_B7 626 L_A2 L_B7 627 L_A3 L_B7 628 L_A4 L_B7 629 L_A5 L_B7 630 L_A6 L_B7 631 L_A7 L_B7 632 L_A8 L_B7 633 L_A9 L_B7 634 L_A10 L_B7 635 L_A11 L_B7 636 L_A12 L_B7 637 L_A13 L_B7 638 L_A14 L_B7 639 L_A15 L_B7 640 L_A16 L_B7 641 L_A17 L_B7 642 L_A18 L_B7 643 L_A19 L_B7 644 L_A20 L_B7 645 L_A21 L_B7 646 L_A22 L_B7 647 L_A23 L_B7 648 L_A24 L_B7 649 L_A25 L_B7 650 L_A26 L_B7 651 L_A27 L_B7 652 L_A28 L_B7 653 L_A29 L_B7 654 L_A30 L_B7 655 L_A31 L_B7 656 L_A32 L_B7 657 L_A33 L_B7 658 L_A34 L_B7 659 L_A35 L_B7 660 L_A36 L_B7 661 L_A37 L_B7 662 L_A38 L_B7 663 L_A39 L_B7 664 L_A40 L_B7 665 L_A41 L_B7 666 L_A42 L_B7 667 L_A43 L_B7 668 L_A44 L_B7 669 L_A45 L_B7 670 L_A46 L_B7 671 L_A47 L_B7 672 L_A48 L_B7 673 L_A49 L_B7 674 L_A50 L_B7 675 L_A51 L_B7 676 L_A52 L_B7 677 L_A53 L_B7 678 L_A54 L_B7 679 L_A55 L_B7 680 L_A56 L_B7 681 L_A57 L_B7 682 L_A58 L_B7 683 L_A59 L_B7 684 L_A60 L_B7 685 L_A61 L_B7 686 L_A62 L_B7 687 L_A63 L_B7 688 L_A64 L_B7 689 L_A65 L_B7 690 L_A66 L_B7 691 L_A67 L_B7 692 L_A68 L_B7 693 L_A69 L_B7 694 L_A70 L_B7 695 L_A71 L_B7 696 L_A72 L_B7 697 L_A73 L_B7 698 L_A74 L_B7 699 L_A75 L_B7 700 L_A76 L_B7 701 L_A77 L_B7 702 L_A78 L_B7 703 L_A79 L_B7 704 L_A80 L_B7 705 L_A81 L_B7 706 L_A82 L_B7 707 L_A83 L_B7 708 L_A84 L_B7 709 L_A85 L_B7 710 L_A86 L_B7 711 L_A87 L_B7 712 L_A88 L_B7 713 L_A89 L_B7 714 L_A90 L_B7 715 L_A91 L_B7 716 L_A92 L_B7 717 L_A93 L_B7 718 L_A94 L_B7 719 L_A95 L_B7 720 L_A96 L_B7 721 L_A97 L_B7 722 L_A98 L_B7 723 L_A99 L_B7 724 L_A100 L_B7 725 L_A101 L_B7 726 L_A102 L_B7 727 L_A103 L_B7 728 L_A104 L_B7 729 L_A1 L_B8 730 L_A2 L_B8 731 L_A3 L_B8 732 L_A4 L_B8 733 L_A5 L_B8 734 L_A6 L_B8 735 L_A7 L_B8 736 L_A8 L_B8 737 L_A9 L_B8 738 L_A10 L_B8 739 L_A11 L_B8 740 L_A12 L_B8 741 L_A13 L_B8 742 L_A14 L_B8 743 L_A15 L_B8 744 L_A16 L_B8 745 L_A17 L_B8 746 L_A18 L_B8 747 L_A19 L_B8 748 L_A20 L_B8 749 L_A21 L_B8 750 L_A22 L_B8 751 L_A23 L_B8 752 L_A24 L_B8 753 L_A25 L_B8 754 L_A26 L_B8 755 L_A27 L_B8 756 L_A28 L_B8 757 L_A29 L_B8 758 L_A30 L_B8 759 L_A31 L_B8 760 L_A32 L_B8 761 L_A33 L_B8 762 L_A34 L_B8 763 L_A35 L_B8 764 L_A36 L_B8 765 L_A37 L_B8 766 L_A38 L_B8 767 L_A39 L_B8 768 L_A40 L_B8 769 L_A41 L_B8 770 L_A42 L_B8 771 L_A43 L_B8 772 L_A44 L_B8 773 L_A45 L_B8 774 L_A46 L_B8 775 L_A47 L_B8 776 L_A48 L_B8 777 L_A49 L_B8 778 L_A50 L_B8 779 L_A51 L_B8 780 L_A52 L_B8 781 L_A53 L_B8 782 L_A54 L_B8 783 L_A55 L_B8 784 L_A56 L_B8 785 L_A57 L_B8 786 L_A58 L_B8 787 L_A59 L_B8 788 L_A60 L_B8 789 L_A61 L_B8 790 L_A62 L_B8 791 L_A63 L_B8 792 L_A64 L_B8 793 L_A65 L_B8 794 L_A66 L_B8 795 L_A67 L_B8 796 L_A68 L_B8 797 L_A69 L_B8 798 L_A70 L_B8 799 L_A71 L_B8 800 L_A72 L_B8 801 L_A73 L_B8 802 L_A74 L_B8 803 L_A75 L_B8 804 L_A76 L_B8 805 L_A77 L_B8 806 L_A78 L_B8 807 L_A79 L_B8 808 L_A80 L_B8 809 L_A81 L_B8 810 L_A82 L_B8 811 L_A83 L_B8 812 L_A84 L_B8 813 L_A85 L_B8 814 L_A86 L_B8 815 L_A87 L_B8 816 L_A88 L_B8 817 L_A89 L_B8 818 L_A90 L_B8 819 L_A91 L_B8 820 L_A92 L_B8 821 L_A93 L_B8 822 L_A94 L_B8 823 L_A95 L_B8 824 L_A96 L_B8 825 L_A97 L_B8 826 L_A98 L_B8 827 L_A99 L_B8 828 L_A100 L_B8 829 L_A101 L_B8 830 L_A102 L_B8 831 L_A103 L_B8 832 L_A104 L_B8 833 L_A1 L_B9 834 L_A2 L_B9 835 L_A3 L_B9 836 L_A4 L_B9 837 L_A5 L_B9 838 L_A6 L_B9 839 L_A7 L_B9 840 L_A8 L_B9 841 L_A9 L_B9 842 L_A10 L_B9 843 L_A11 L_B9 844 L_A12 L_B9 845 L_A13 L_B9 846 L_A14 L_B9 847 L_A15 L_B9 848 L_A16 L_B9 849 L_A17 L_B9 850 L_A18 L_B9 851 L_A19 L_B9 852 L_A20 L_B9 853 L_A21 L_B9 854 L_A22 L_B9 855 L_A23 L_B9 856 L_A24 L_B9 857 L_A25 L_B9 858 L_A26 L_B9 859 L_A27 L_B9 860 L_A28 L_B9 861 L_A29 L_B9 862 L_A30 L_B9 863 L_A31 L_B9 864 L_A32 L_B9 865 L_A33 L_B9 866 L_A34 L_B9 867 L_A35 L_B9 868 L_A36 L_B9 869 L_A37 L_B9 870 L_A38 L_B9 871 L_A39 L_B9 872 L_A40 L_B9 873 L_A41 L_B9 874 L_A42 L_B9 875 L_A43 L_B9 876 L_A44 L_B9 877 L_A45 L_B9 878 L_A46 L_B9 879 L_A47 L_B9 880 L_A48 L_B9 881 L_A49 L_B9 882 L_A50 L_B9 883 L_A51 L_B9 884 L_A52 L_B9 885 L_A53 L_B9 886 L_A54 L_B9 887 L_A55 L_B9 888 L_A56 L_B9 889 L_A57 L_B9 890 L_A58 L_B9 891 L_A59 L_B9 892 L_A60 L_B9 893 L_A61 L_B9 894 L_A62 L_B9 895 L_A63 L_B9 896 L_A64 L_B9 897 L_A65 L_B9 898 L_A66 L_B9 899 L_A67 L_B9 900 L_A68 L_B9 901 L_A69 L_B9 902 L_A70 L_B9 903 L_A71 L_B9 904 L_A72 L_B9 905 L_A73 L_B9 906 L_A74 L_B9 907 L_A75 L_B9 908 L_A76 L_B9 909 L_A77 L_B9 910 L_A78 L_B9 911 L_A79 L_B9 912 L_A80 L_B9 913 L_A81 L_B9 914 L_A82 L_B9 915 L_A83 L_B9 916 L_A84 L_B9 917 L_A85 L_B9 918 L_A86 L_B9 919 L_A87 L_B9 920 L_A88 L_B9 921 L_A89 L_B9 922 L_A90 L_B9 923 L_A91 L_B9 924 L_A92 L_B9 925 L_A93 L_B9 926 L_A94 L_B9 927 L_A95 L_B9 928 L_A96 L_B9 929 L_A97 L_B9 930 L_A98 L_B9 931 L_A99 L_B9 932 L_A100 L_B9 933 L_A101 L_B9 934 L_A102 L_B9 935 L_A103 L_B9 936 L_A104 L_B9

In some embodiments, the compound is selected from the group consisting of:

According to another aspect of the present disclosure, a first device is also provided. The first device includes a first organic light emitting device, that includes an anode, a cathode, and an organic layer disposed between the anode and the cathode. The organic layer may include a host and a phosphorescent dopant. The emissive layer can include a compound having a structure according to formula M(L_A)_x(L_B)_y(L_C)_z, and its variations as described herein.

The first device can be one or more of a consumer product, an organic light-emitting device and a lighting panel. The organic layer can be an emissive layer and the compound can be an emissive dopant in some embodiments, while the compound can be a non-emissive dopant in other embodiments.

The organic layer can also include a host. In some embodiments, the host can include a metal complex. The host can be a triphenylene containing benzo-fused thiophene or benzo-fused furan. Any substituent in the host can be an unfused substituent independently selected from the group consisting of C_nH_2n+1, OC_nH_2n+1, OAr₁, N(C_nH_2n+1)₂, N(Ar₁)(Ar₂), CH═CH—C_nH_2n+1, C≡C—C_nH_2n+1, Ar₁, Ar₁—Ar₂, C_nH_2n—Ar₁, or no substitution. In the preceding substituents n can range from 1 to 10; and Ar₁and Ar₂can be independently selected from the group consisting of benzene, biphenyl, naphthalene, triphenylene, carbazole, and heteroaromatic analogs thereof.

The host can be a compound selected from the group consisting of carbazole, dibenzothiophene, dibenzofuran, dibenzoselenophene, azacarbazole, aza-dibenzothiophene, aza-dibenzofuran, and aza-dibenzoselenophene. The host can include a metal complex. The host can be a specific compound selected from the group consisting of:

and combinations thereof.

In yet another aspect of the present disclosure, a formulation that comprises a compound having a structure according to formula M(L_A)_x(L_B)_y(L_C)_z, and its variations as described herein is disclosed The formulation can include one or more components selected from the group consisting of a solvent, a host, a hole injection material, hole transport material, and an electron transport layer material, disclosed herein.

Combination with Other Materials

The materials described herein as useful for a particular layer in an organic light emitting device may be used in combination with a wide variety of other materials present in the device. For example, emissive dopants disclosed herein may be used in conjunction with a wide variety of hosts, transport layers, blocking layers, injection layers, electrodes and other layers that may be present. The materials described or referred to below are non-limiting examples of materials that may be useful in combination with the compounds disclosed herein, and one of skill in the art can readily consult the literature to identify other materials that may be useful in combination.

HIL/HTL:

A hole injecting/transporting material to be used in the present invention is not particularly limited, and any compound may be used as long as the compound is typically used as a hole injecting/transporting material. Examples of the material include, but not limit to: a phthalocyanine or porphyrin derivative; an aromatic amine derivative; an indolocarbazole derivative; a polymer containing fluorohydrocarbon; a polymer with conductivity dopants; a conducting polymer, such as PEDOT/PSS; a self-assembly monomer derived from compounds such as phosphonic acid and silane derivatives; a metal oxide derivative, such as MoO_x; a p-type semiconducting organic compound, such as 1,4,5,8,9,12-Hexaazatriphenylenehexacarbonitrile; a metal complex, and a cross-linkable compounds.

Examples of aromatic amine derivatives used in HIL or HTL include, but not limit to the following general structures:

Each of Ar¹to Ar⁹is selected from the group consisting aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene; group consisting aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and group consisting 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Wherein each Ar is further substituted by a substituent selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

In one aspect, Ar¹to Ar⁹is independently selected from the group consisting of:

wherein k is an integer from 1 to 20; X¹⁰¹to X¹⁰⁸is C (including CH) or N; Z¹⁰¹is NAr¹, O, or S; Ar¹has the same group defined above.

Examples of metal complexes used in HIL or HTL include, but not limit to the following general formula:

wherein Met is a metal, which can have an atomic weight greater than 40; (Y¹⁰¹-Y¹⁰²) is a bidentate ligand, Y¹⁰¹and Y¹⁰²are independently selected from C, N, O, P, and S; L¹⁰¹is an ancillary ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.

In one aspect, (Y¹⁰¹-Y¹⁰²) is a 2-phenylpyridine derivative. In another aspect, (Y¹⁰¹-Y¹⁰²) is a carbene ligand. In another aspect, Met is selected from Ir, Pt, Os, and Zn. In a further aspect, the metal complex has a smallest oxidation potential in solution vs. Fc⁺/Fc couple less than about 0.6 V.

Host:

The light emitting layer of the organic EL device of the present invention preferably contains at least a metal complex as light emitting material, and may contain a host material using the metal complex as a dopant material. Examples of the host material are not particularly limited, and any metal complexes or organic compounds may be used as long as the triplet energy of the host is larger than that of the dopant. While the Table below categorizes host materials as preferred for devices that emit various colors, any host material may be used with any dopant so long as the triplet criteria is satisfied.

Examples of metal complexes used as host are preferred to have the following general formula:

wherein Met is a metal; (Y¹⁰³-Y¹⁰⁴) is a bidentate ligand, Y¹⁰³and Y¹⁰⁴are independently selected from C, N, O, P, and S; L¹⁰¹is an another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal; and k′+k″ is the maximum number of ligands that may be attached to the metal.

In one aspect, the metal complexes are:

wherein (O—N) is a bidentate ligand, having metal coordinated to atoms O and N.

In another aspect, Met is selected from Ir and Pt. In a further aspect, (Y¹⁰³-Y¹⁰⁴) is a carbene ligand.

Examples of organic compounds used as host are selected from the group consisting aromatic hydrocarbon cyclic compounds such as benzene, biphenyl, triphenyl, triphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chrysene, perylene, azulene; group consisting aromatic heterocyclic compounds such as dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridylindole, pyrrolodipyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, oxatriazole, dioxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indole, benzimidazole, indazole, indoxazine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, phenoxazine, benzofuropyridine, furodipyridine, benzothienopyridine, thienodipyridine, benzoselenophenopyridine, and selenophenodipyridine; and group consisting 2 to 10 cyclic structural units which are groups of the same type or different types selected from the aromatic hydrocarbon cyclic group and the aromatic heterocyclic group and are bonded to each other directly or via at least one of oxygen atom, nitrogen atom, sulfur atom, silicon atom, phosphorus atom, boron atom, chain structural unit and the aliphatic cyclic group. Wherein each group is further substituted by a substituent selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.

In one aspect, host compound contains at least one of the following groups in the molecule:

wherein R¹⁰¹to R¹⁰⁷independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl heteroalkenyl alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above. k is an integer from 0 to 20 or 1 to 20; k′″ is an integer from 0 to 20. X¹⁰¹to X¹⁰⁸is selected from C (including CH) or N. Z¹⁰¹and Z¹⁰²is selected from NR¹⁰¹, O, or S.
HBL:

A hole blocking layer (HBL) may be used to reduce the number of holes and/or excitons that leave the emissive layer. The presence of such a blocking layer in a device may result in substantially higher efficiencies as compared to a similar device lacking a blocking layer. Also, a blocking layer may be used to confine emission to a desired region of an OLED.

In one aspect, compound used in HBL contains the same molecule or the same functional groups used as host described above.

In another aspect, compound used in HBL contains at least one of the following groups in the molecule:

wherein k is an integer from 1 to 20; L¹⁰¹is an another ligand, k′ is an integer from 1 to 3.
ETL:

Electron transport layer (ETL) may include a material capable of transporting electrons. Electron transport layer may be intrinsic (undoped), or doped. Doping may be used to enhance conductivity. Examples of the ETL material are not particularly limited, and any metal complexes or organic compounds may be used as long as they are typically used to transport electrons.

In one aspect, compound used in ETL contains at least one of the following groups in the molecule:

wherein R¹⁰¹is selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof, when it is aryl or heteroaryl, it has the similar definition as Ar's mentioned above. Ar¹to Ar³has the similar definition as Ar's mentioned above. k is an integer from 1 to 20. X¹⁰¹to X¹⁰⁸is selected from C (including CH) or N.

In another aspect, the metal complexes used in ETL contains, but not limit to the following general formula:

wherein (O—N) or (N—N) is a bidentate ligand, having metal coordinated to atoms O, N or N, N; L¹⁰¹is another ligand; k′ is an integer value from 1 to the maximum number of ligands that may be attached to the metal.

In any above-mentioned compounds used in each layer of the OLED device, the hydrogen atoms can be partially or fully deuterated. Thus, any specifically listed substituent, such as, without limitation, methyl, phenyl, pyridyl, etc. encompasses undeuterated, partially deuterated, and fully deuterated versions thereof. Similarly, classes of substituents such as, without limitation, alkyl, aryl, cycloalkyl, heteroaryl, etc. also encompass undeuterated, partially deuterated, and fully deuterated versions thereof.

In addition to and/or in combination with the materials disclosed herein, many hole injection materials, hole transporting materials, host materials, dopant materials, exiton/hole blocking layer materials, electron transporting and electron injecting materials may be used in an OLED. Non-limiting examples of the materials that may be used in an OLED in combination with materials disclosed herein are listed in Table A below. Table A lists non-limiting classes of materials, non-limiting examples of compounds for each class, and references that disclose the materials.

TABLE A MATERIAL EXAMPLES OF MATERIAL PUBLICATIONS Hole injection materials Phthalocyanine and porphyrin compounds Appl, Phys. Lett. 69, 2160 (1996) Starburst triarylamines J. Lumin, 72-74, 985 (1997) CF_xFluorohydrocarbon polymer Appl. Phys. Lett. 78, 673 (2001) Conducting polymers (e.g., PEDOT:PSS, polyaniline, polythiophene) Synth. Met. 87, 171 (1997) WO2007002683 Phosphonic acid and silane SAMs US20030162053 Triarylamine or polythiophene polymers with conductivity dopants EP1725079A1 Organic compounds with conductive inorganic compounds, such as molybdenum and tungsten oxides US20050123751 SID Symposium Digest, 37, 923 (2006) WO2009018009 n-type semiconducting organic complexes US20020158242 Metal organometallic complexes US20060240279 Cross-linkable compounds US20080220265 Polythiophene based polymers and copolymers WO 2011075644 EP2350216 Hole transporting materials Triarylamines (e.g., TPD, α-NPD) Appl. Phys. Lett. 51, 913 (1987) U.S. Pat. No. 5,061,569 EP650955 J. Mater. Chem. 3, 319 (1993) Appl. Phys. Lett. 90, 183503 (2007) Appl. Phys. Lett. 90, 183503 (2007) Triarylamine on spirofluorene core Synth. Met. 91, 209 (1997) Arylamine carbazole compounds Adv. Mater. 6, 677 (1994), US20080124572 Triarylamine with (di)benzothiophene/ (di)benzofuran US20070278938, US20080106190 US20110163302 Indolocarbazoles Synth. Met. 111, 421 (2000) Isoindole compounds Chem. Mater. 15, 3148 (2003) Metal carbene complexes US20080018221 Phosphorescent OLED host materials Red hosts Arylcarbazoles Appl. Phys. Lett. 78, 1622 (2001) Metal 8-hydroxyquinolates (e.g., Alq₃, BAlq) Nature 395, 151 (1998) US20060202194 WO2005014551 WO2006072002 Metal phenoxybenzothiazole compounds Appl. Phys. Lett. 90, 123509 (2007) Conjugated oligomers and polymers (e.g., polyfluorene) Org. Electron. 1, 15 (2000) Aromatic fused rings WO2009066779, WO2009066778, WO2009063833, US20090045731, US20090045730, WO2009008311, US20090008605, US20090009065 Zinc complexes WO2010056066 Chrysene based compounds WO2011086863 Green hosts Arylcarbazoles Appl. Phys. Lett. 78, 1622 (2001) US20030175553 WO2001039234 Aryltriphenylene compounds US20060280965 US20060280965 WO2009021126 Poly-fused heteroaryl compounds US20090309488 US20090302743 US20100012931 Donor acceptor type molecules WO2008056746 WO2010107244 Aza-carbazole/DBT/DBF JP2008074939 US2010187984 Polymers (e.g., PVK) Appl. Phys. Lett. 77, 2280 (2000) Spirofluorene compounds WO2004093207 Metal phenoxybenzooxazole compounds WO2005089025 WO2006132173 JP200511610 Spirofluorene-carbazole compounds JP2007254297 JP2007254297 Indolocarbazoles WO2007063796 WO2007063754 5-member ring electron deficient heterocycles (e.g., triazole, oxadiazole) J. Appl. Phys. 90, 5048 (2001) WO2004107822 Tetraphenylene complexes US20050112407 Metal phenoxypyridine compounds WO2005030900 Metal coordination complexes (e.g., Zn, Al with N{circumflex over ( )}N ligands) US20040137268, US20040137267 Blue hosts Arylcarbazoles Appl. Phys. Lett, 82, 2422 (2003) US20070190359 Dibenzothiophene/ Dibenzofuran-carbazole compounds WO2006114966, US20090167162 US20090167162 WO2009086028 US20090030202, US20090017330 US20100084966 Silicon aryl compounds US20050238919 WO2009003898 Silicon/Germanium aryl compounds EP2034538A Aryl benzoyl ester WO2006100298 Carbazole linked by non- conjugated groups US20040115476 Aza-carbazoles US20060121308 High triplet metal organometallic complex U.S. Pat. No. 7,154,114 Phosphorescent dopants Red dopants Heavy metal porphyrins (e.g., PtOEP) Nature 395, 151 (1998) Iridium(III) organometallic complexes Appl. Phys. Lett. 78, 1622 (2001) US20030072964 US20030072964 US20060202194 US20060202194 US20070087321 US20080261076 US20100090591 US20070087321 Adv. Mater. 19, 739 (2007) WO2009100991 WO2008101842 U.S. Pat. No. 7,232,618 Platinum( I I ) organometallic complexes WO2003040257 US20070103060 Osmium(III) complexes Chem. Mater. 17, 3532 (2005) Ruthenium (II) complexes Adv. Mater. 17, 1059 (2005) Rhenium (I), (II), and (III) complexes US20050244673 Green dopants Iridium(III) organometallic complexes Inorg. Chem. 40, 1704 (2001) and its derivatives US20020034656 U.S. Pat. No. 7,332,232 US20090108737 WO2010028151 EP1841834B US20060127696 US20090039776 U.S. Pat. No. 6,921,915 US20100244004 U.S. Pat. No. 6,687,266 Chem. Mater. 16, 2480 (2004) US20070190359 US 20060008670 JP2007123392 WO2010086089, WO2011044988 Adv. Mater. 16, 2003 (2004) Angew. Chem. Int . Ed. 2006, 45, 7800 WO2009050290 US20090165846 US20080015355 US20010015432 US20100295032 Monomer for polymeric metal organometallic compounds U.S. Pat. No. 7,250,226, U.S. Pat. No. 7,396,598 Pt(II) organometallic complexes, including polydentated ligands Appl. Phys. Lett. 86, 153505 (2005) Appl. Phys. Lett 86, 153505 (2005) Chem. Lett. 34, 592 (2005) WO2002015645 US20060263635 US20060182992 US20070103060 Cu complexes WO2009000673 US20070111026 Gold complexes Chem. Commun. 2906 (2005) Rhenium(III) complexes Inorg. Chem. 42, 1248 (2003) Osmium(II) complexes U.S. Pat. No. 7,279,704 Deuterated organometallic complexes US20030138657 Organometallic complexes with two or more metal centers US20030152802 U.S. Pat. No. 7,090,928 Blue dopants Iridium(III) organometallic complexes WO2002002714 WO2006009024 US20060251923 US20110057559 US20110204333 U.S. Pat. No. 7,393,599, WO2006056418, US20050260441, WO2005019373 U.S. Pat. No. 7,534,505 WO2011051404 U.S. Pat. No. 7,445,855 US20070190359, US20080297033 US20100148663 U.S. Pat. No. 7,338,722 US20020134984 Angew. Chem. Int. Ed. 47, 4542 (2008) Chem. Mater. 18, 5119 (2006) Inorg. Chem. 46, 4308 (2007) WO2005123873 WO2005123873 WO2007004380 WO2006082742 Ostnium(II) complexes U.S. Pat. No. 7,279,704 Organometallics 23, 3745 (2004) Gold complexes Appl. Phys. Lett. 74, 1361 (1999) Platinum(II) complexes WO2006098120, WO2006103874 Pt tetradentate complexes with at least one metal- carbene bond U.S. Pat. No. 7,655,323 Exciton/hole blocking layer materials Bathocuprine compounds (e.g., BCP, BPhen) Appl. Phys. Lett. 75, 4 (1999) Appl. Phys. Lett. 79, 449 (2001) Metal 8-hydroxyquinolates (e.g., BAlq) Appl. Phys. Lett. 81, 162 (2002) 5-member ring electron deficient heterocycles such as triazole, oxadiazole, imidazole, benzoimidazole Appl. Phys. Lett. 81, 162 (2002) Triphenylene compounds US20050025993 Fluorinated aromatic compounds Appl. Phys. Lett. 79, 156 (2001) Phenothiazine-S-oxide WO2008132085 Silylated five-membered nitrogen, oxygen, sulfur or phosphorus dibenzoheterocycles WO2010079051 Aza-carbazoles US20060121308 Electron transporting materials Anthracene- benzoimidazole compounds WO2003060956 US20090179554 Aza triphenylene derivatives US20090115316 Anthracene- benzothiazole compounds Appl. Phys. Lett. 89, 063504 (2006) Metal 8-hydroxyquinolates (e.g., Alq₃, Zrq₄) Appl. Phys. Lett. 51, 913 (1987) U.S. Pat. No. 7,230,107 Metal hydroxybenzoquinolates Chem. Lett. 5, 905 (1993) Bathocuprine compounds such as BCP, BPhen, etc Appl. Phys. Lett. 91, 263503 (2007) Appl. Phys. Lett. 79, 449 (2001) 5-member ring electron deficient heterocycles (e.g., triazole, oxadiazole, imidazole, benzoimidazole) Appl. Phys. Lett. 74, 865 (1999) Appl. Phys. Lett. 55, 1489 (1989) Jpn. J. Apply. Phys. 32, L917 (1993) Silole compounds Org. Electron. 4, 113 (2003) Arylborane compounds J. Am. Chem. Soc. 120, 9714 (1998) Fluorinated aromatic compounds J. Am. Chem. Soc. 122, 1832 (2000) Fullerene (e.g., C60) US20090101870 Triazine complexes US20040036077 Zn (N{circumflex over ( )}N) complexes U.S. Pat. No. 6,528,187

EXPERIMENTAL

Materials Synthesis

All reactions were carried out under nitrogen protections unless specified otherwise. All solvents for reactions are anhydrous and used as received from commercial sources.

Synthesis of Comparative Compound 1

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-5-phenylquinoline

Pd₂dba₃(0.24 g, 0.26 mmol) dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (SHOS) (0.43 g, 1.05 mmol), 5-chloro-2-(3,5-dimethylphenyl)quinoline (3.50 g, 13.1 mmol), phenylboronic acid (2.39 g, 19.6 mmol), and potassium phosphate (K₃PO₄) (5.55 g, 26.1 mmol) were diluted with 110 mL of dimethoxyethane (DME) and 22 mL of water. The solution was bubbled with nitrogen gas for 20 minutes and the reaction mixture was maintained at reflux for 12 hours. Upon completion, 100 mL of toluene was added and the mixture was extracted 3 times with 100 mL of dichloromethane (DCM), then dried over sodium sulfate, and evaporated. The crude product was purified via column chromatography using Heptanes/ethyl acetate (EA) (100/0 to 90/10) solvent system. The yellowish oil was solidified in heptanes. The filtered solids were triturated from methanol to afford the pure 2-(3,5-dimethylphenyl)-5-phenylquinoline (2.6 g, 65% yield).

Step 2:

Synthesis of Ir(III) Dimer

Iridium chloride hydrate (0.78 g, 2.10 mmol) and 2-(3,5-dimethylphenyl)-5-phenylquinoline (2.6 g, 8.40 mmol) were diluted in 24 ml 2-ethoxyethanol and 8 mL of water. The mixture was degassed by bubbling nitrogen for 20 minutes and the reaction was maintained at 105° C. for 24 hours. The reaction mixture was then cooled to 0° C. and filtered. The solid was washed with cold ethanol and dried to afford 1.6 g (85% yield) of the dimer.

Step 3:

Synthesis of Comparative Compound 1

A mixture of the Ir(III) dimer of step 2 (1.60 g, 0.95 mmol) from step 2, and 3,7-diethylnonane-4,6-dione (2.01 g, 9.47 mmol) were diluted in 20 mL 2-ethoxyethanol, and the mixture was degassed by bubbling nitrogen gas for 20 minutes. Potassium carbonate (1.31 g, 9.47 mmol) was then added and the reaction mixture was stirred at room temperature overnight. Upon completion, the reaction was diluted with dichloromethane (DCM), filtered through a pad of Celite and washed with more DCM. The crude material was purified via column chromatography (silica pre-treated with triethylamine) using a Heptanes/DCM (100/0 to 97/3) solvent system. The evaporated pure fractions were triturated in methanol which afforded 1.3 g (68% yield) of pure comparative compound 1.

Synthesis of Comparative Compound 2

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-5-(4-isopropylphenyl)quinoline

5-chloro-2-(3,5-dimethylphenyl)quinoline (3.75 g, 14.0 mmol), (4-isopropylphenyl)boronic acid (2.76 g, 16.8 mmol), Pd₂dba₃(0.26 g, 0.28 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (SPhos) (0.46 g, 1.12 mmol), and K₃PO₄(5.95 g, 28.0 mmol) were diluted in toluene (120 mL) and water (25 mL). The mixture was degassed by bubbling nitrogen gas for 15 minutes and then the reaction mixture was refluxed overnight. Upon completion, the reaction mixture was cooled to room temperature, then extracted with toluene, and washed with water and brine. The crude product was purified via column chromatography using a heptanes/ethyl acetate (95/5) solvent system. The white powder was recrystallized from heptanes to isolate 2-(3,5-dimethylphenyl)-5-(4-isopropylphenyl)quinoline (3.0 g, 61% yield) as white crystals.

Step 2:

Synthesis of Ir(III) Dimer

2-(3,5-dimethylphenyl)-5-(4-isopropylphenyl)quinoline (1.10 g, 3.13 mmol) was solubilized in 2-ethoxyethanol (12 mL) and water (4 mL). The mixture was degassed with nitrogen for 30 minutes. Iridium chloride hydrate (0.36 g, 0.96 mmol) was then added to the solution (some ligand precipitated) and the reaction was refluxed under nitrogen for 24 h. After cooling, the solid was filtered, washed with methanol, and dried to yielded the Ir(III) dimer (0.65 g, 73% yield) as a dark red powder.

Step 3:

Synthesis of Comparative Compound 2

Ir(III) dimer of step 2 (0.65 g, 0.35 mmol) and pentane-2,4-dione (0.35 g, 3.50 mmol) were diluted in 2-Ethoxyethanol (12 mL). The mixture was then degassed by bubbling nitrogen gas through it. K₂CO₃(0.48 g, 3.50 mmol) was then added and the reaction mixture was stirred at room temperature overnight. The reaction mixture was diluted with DCM, filtered through a pad of Celite, and washed with DCM. The crude material was purified by column chromatography (silica pre-treated with TEA) using a heptanes/DCM (95/5 to 90/10)) solvent system. The combined fractions were triturated from methanol and the solids were recrystallized from DCM/methanol two times. Comparative compound 2 was isolated as a red powder. (0.4 g, 58% yield).

Synthesis of Comparative Compound 3

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-7-phenylquinoline

7-chloro-2-(3,5-dimethylphenyl)quinoline (3.5 g, 13.1 mmol), phenylboronic acid (2.39 g, 19.6 mmol), Pd₂dba₃(0.24 g, 0.26 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (0.43 g, 1.05 mmol), and K₃PO₄(5.55 g, 26.1 mmol) were inserted in a round bottom flask (RBF) and diluted with DME (110 mL) and Water (22 mL). The reaction was degassed by bubbling nitrogen gas for 15 minutes and then heated to reflux overnight. The mixture was then cooled to room temperature and extracted with ethyl alcohol (EA). The crude material was purified by column chromatography using a heptanes/EA (95/5) solvent system. The collected fractions were triturated with MeOH to afford 2-(3,5-dimethylphenyl)-5-phenylquinoline (3.4 g, 85% yield) as a white powder.

Step 2:

Synthesis of Ir(III) Dimer

2-(3,5-dimethylphenyl)-7-phenylquinoline (3.35 g, 10.8 mmol) was solubilized in ethoxyethanol (25 mL) and water (8 mL) and degassed by bubbling nitrogen gas for 30 minutes. Iridium chloride hydrate (1.00 g, 2.71 mmol) was then added to the mixture, which was then heated to reflux under nitrogen for 24 h. After cooling the mixture to room temperature, the solid was filtered, washed with methanol, and dried to give the Ir(III) Dimer (1.8 g 79% yield) as a red powder.

Step 3:

Synthesis of Comparative Compound 3

The Ir(III) dimer of step 2 (1.9 g, 1.13 mmol) and 3,7-diethylnonane-4,6-dione (2.39 g, 11.3 mmol) were diluted in 2-ethoxyethanol (40 mL), and the mixture was degassed by bubbling nitrogen gas for 15 minutes. Potassium carbonate (1.56 g, 11.3 mmol) was then added and the reaction was stirred at room temperature overnight. Upon completion of the reaction, the mixture was diluted with DCM, filtered through a plug of Celite, and washed with DCM. The crude material was purified by column chromatography (silica gel pre-treated with triethylamine) using a heptanes/DCM (95/5) solvent system. The collected fractions were titurated with MeOH. A red powder was recrystallized from a MeOH/DCM solvent system to afford 1.5 g (63% yield) of comparative compound 3 as red crystals.

Synthesis of Compound 28

Step 1:

Synthesis of Compound 28

Ir(III) dimer of step 2 of the synthesis of comparative compound 2 (1.50 g, 0.81 mmol), above, and 3,7-diethylnonane-4,6-dione (1.72 g, 8.1 mmol) were diluted in ethoxyethanol (27 mL). The mixture was then degassed by bubbling nitrogen gas. K₂CO (1.12 g, 8.1 mmol) was then added, and the reaction mixture was stirred at room temperature overnight. The mixture was diluted with DCM, filtered through a pad of Celite, and washed with DCM. The crude material was purified via column chromatography (silica pre-treated with triethylamine) using a heptanes/DCM 80/20 solvent system. The collected pure fractions were triturated from methanol, and the solids were recrystallized from DCM/methanol two times to yield compound 28 as dark red crystals (1.3 g, 73% yield).

Synthesis of Compound 80

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-7-(4-Isopropylphenyl)quinoline

7-chloro-2-(3,5-dimethylphenyl)quinoline (4.25 g, 15.9 mmol), (4-isopropylphenyl)boronic acid (3.12 g, 19.1 mmol), Pd₂dba₃(0.29 g, 0.32 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (SPhos) (0.52 g, 1.27 mmol), and K₃PO₄(6.74 g, 31.7 mmol) were solubilized in toluene (130 mL) and water (27 mL). The reaction mixture was degassed by bubbling nitrogen gas through it for 15 minutes, then the reaction mixture was heated to reflux overnight. Upon completion, the reaction mixture was cooled to room temperature, extracted with ethyl acetate, and washed with brine and water. The crude product was purified via column chromatography using a heptanes/ethyl acetate (97/3 to 95/5) solvent system. The product was then recrystallized from heptanes/DCM to isolate 2-(3,5-dimethylphenyl)-7-(4-isopropylphenyl)quinoline (2.5 g, 45% yield) of pure ligand.

Step 2:

Synthesis of Ir(III) Dimer

2-(3,5-dimethylphenyl)-7-(4-isopropylphenyl)quinoline (2.25 g, 6.40 mmol) was solubilized in ethoxyethanol (23 mL) and water (8 mL), then the mixture was degassed with nitrogen gas for 30 minutes. Iridium chloride hydrate (0.68 g, 1.83 mmol) was then added to the reaction mixture, and the reaction mixture was refluxed under nitrogen for 24 h. After cooling to room temperature, the solid was filtered, washed with methanol and dried to give Ir(III) dimer (1.2 g, 71% yield) as a brown powder.

Step 3:

Synthesis of Compound 80

The Ir(III) dimer of step 2 (1.1 g, 0.59 mmol) and 3,7-diethylnonane-4,6-dione (1.26 g, 5.92 mmol) were diluted in ethoxyethanol (20 mL), then the reaction mixture was degassed by bubbling nitrogen gas through it. K₂CO (0.82 g, 5.92 mmol) was then added to the reaction mixture, and the reaction mixture was stirred at room temperature overnight. The reaction mixture was diluted with DCM, filtered through a pad of Celite, and washed with DCM. The crude material was purified by column chromatography (silica pre-treated with TEA) using a heptanes/DCM (95/5) solvent system. The collected pure fractions were triturated from methanol and the solids were recrystallized from DCM/MeOH. Compound 80 was isolate as a dark red solid (1.0 g, 76% yield).

Synthesis of Compound 81

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-7-(4-isobutylphenyl)quinoline

7-chloro-2-(3,5-dimethylphenyl)quinoline (3.5 g, 13.1 mmol), (4-isobutylphenyl)boronic acid (3.49 g, 19.6 mmol), Pd₂dba₃(0.24 g, 0.26 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (SPhos) (0.43 g, 1.05 mmol), and K₃PO₄(5.55 g, 26.1 mmol) were diluted in toluene (110 mL) and water (20 mL). The reaction mixture was degassed by bubbling nitrogen through it for 15 minutes. The reaction mixture was then heated to reflux overnight. Upon completion, the mixture was cooled, extracted with EA and washed with water. The crude product was purified by column chromatography using a heptanes/EA (95/5) solvent system. The collected product was triturated from heptanes to isolate pure 2-(3,5-dimethylphenyl)-7-(4-isobutylphenyl)quinoline (3.10 g, 65% yield) as a white powder.

Step 2:

Synthesis of Ir(III) Dimer

2-(3,5-dimethylphenyl)-7-(4-isobutylphenyl)quinoline (3.2 g, 8.75 mmol) was solubilized in ethoxyethanol (27 mL) and water (9 mL), then degassed with nitrogen for 30 minutes. Iridium chloride hydrate (0.81 g, 2.19 mmol) was then added to the reaction mixture, and the reaction mixture was refluxed under nitrogen for 24 h. After cooling to room temperature, the solid was filtered, washed with methanol, and dried to give Ir(III) dimer (1.55 g, 74% yield) as a red powder. There was still ligand left, but the product was used without further purification.

Step 3:

Synthesis of Compound 81

The Ir(III) dimer of step 2 (1.50 g, 0.78 mmol) and 3,7-diethylnonane-4,6-dione (1.67 g, 7.84 mmol) were diluted in ethoxyethanol (26 mL), then the mixture was degassed by bubbling nitrogen gas through it. K₂CO₃(1.08 g, 7.84 mmol) was then added and the reaction mixture was stirred at room temperature overnight. The reaction mixture was diluted with DCM, filtered through a pad of Celite, and washed with DCM. The crude material was purified by column chromatography (silica pre-treated with TEA) using a heptanes/DCM (90/10) solvent system. The collected pure fractions were triturated from methanol and the solids were recrystallized from DCM/methanol. Compound 81 was isolated as a red powder (1.25 g, 70% yield).

Synthesis of Compound 84

Step 1:

Synthesis of 2-(3,5-dimethylphenyl)-7-(4-fluorophenyl)quinoline

7-chloro-2-(3,5-dimethylphenyl)quinoline (4 g, 14.94 mmol), (4-fluorophenyl)boronic acid (2.508 g, 17.93 mmol), Pd2(dba)3 (0.274 g, 0.299 mmol), dicyclohexyl(2′,6′-dimethoxy-[1,1′-biphenyl]-2-yl)phosphine (0.491 g, 1.195 mmol), potassium phosphate (7.93 g, 37.3 mmol), toluene (100 mL) and water (20 mL) were combined in a flask. A condenser was attached then the system, which was evacuated and purged with nitrogen three times. The reaction mixture was heated to reflux overnight. After cooling, the reaction mixture was filtered through celite using ethyl acetate. After the aqueous was partitioned off, the organic portion was washed with brine once, dried with sodium sulfate, filtered, and concentrated down to 5.8 g of a brown solid. The sample was purified with silica gel using a heptane/DCM (50/50) solvent system to get 4.5 g of a white solid. HPLC indicated it was 99.7% pure. 125 ml heptane was added to the 4.5 g sample, then DCM until the solids dissolved. The solution was heated to reflux to remove the DCM. A white precipitate formed immediately upon cooling. The sample was allowed to stand for two hours, then the precipitate was filtered off to get 3.88 g of a white solid for a 79% yield of 2-(3,5-dimethylphenyl)-7-(4-fluorophenyl)quinoline.

Step 2:

Synthesis of Ir(III) Dimer

2-(3,5-dimethylphenyl)-7-(4-fluorophenyl)quinoline (3.00 g, 9.16 mmol) was solubilized in ethoxyethanol (29 mL) and water (10 mL), then the mixture was degassed with nitrogen for 30 minutes. Iridium chloride hydrate (0.85 g, 2.29 mmol) was then added to the reaction mixture, and the reaction mixture was refluxed under nitrogen for 24 h. After cooling to room temperature, the solid was filtered, washed with methanol, and dried to yield the Ir(III) dimer (2.70 g, 134% yield) as a red powder. There was still ligand left but the product was used without further purification. The true yield of the reaction is believed to be around 50-60%.

Step 3:

Synthesis of Compound 84

The Ir(III) dimer of step 2 (2.70 g, 1.53 mmol), 3,7-diethylnonane-4,6-dione (3.26 g, 15.3 mmol), and 2-ethoxyethanol (40 mL) were combined in a 100 ml single neck round bottom flask. Nitrogen was bubbled directly into the solution for 15 min. Potassium carbonate (2.12 g, 15.3 mmol) was added, then the system was placed under nitrogen and stirred at room temperature overnight. Next morning, TLC indicated a product had formed. The reaction was filtered through celite using DCM until the red color came off. The solution was concentrated down to a dark red oil. The sample was purified with silica gel, preconditioned with heptane/triethyl amine; DCM (60/20/20), then heptane/DCM (90/10), using a heptanes/DCM (90/10) solvent system. Fractions containing the dark red color were combined and concentrated down to 2.70 g of a dark red solid. To remove the ligand, the sample was triturated in 100 ml refluxing methanol, then the insoluble red precipitate was filtered off while the methanol was still hot to get 0.88 g of a red solid. The trituration was repeated with 75 ml hot methanol and the filtered red solid was dried in a vacuum oven overnight to get 0.80 g of a red solid for a 49.4% yield of compound 84.

Device Examples

All example devices were fabricated by high vacuum (<10⁻⁷Torr) thermal evaporation. The anode electrode was 1200 Å of indium tin oxide (ITO). The cathode consisted of 10 Å of LiF followed by 1,000 Å of Al. All devices were encapsulated with a glass lid sealed with an epoxy resin in a nitrogen glove box (<1 ppm of H₂O and O₂) immediately after fabrication, and a moisture getter was incorporated inside the package. The organic stack of the device examples consisted of sequentially, from the ITO surface, 100 Å of LG101 (purchased from LG chem) as the hole injection layer (HIL); 400 Å of 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPD) as the hole transporting layer (HTL); 300 Å of an emissive layer (EML) containing Compound H as a host (79%), a stability dopant (SD) (18%), and Compound 28, Compound 80, Compound 81, or Compound 84 as an emitter; 100 Å of Compound H as a blocking layer; and 450 Å of Alq₃(tris-8-hydroxyquinoline aluminum) as the ETL. The emitter was selected to provide the desired color and the stability dopant (SD) was mixed with the electron-transporting host and the emitter to help transport positive charge in the emissive layer. The Comparative Example devices were fabricated similarly to the device examples except that Comparative Compounds 1, 2, and 3 were used as the emitter in the EML. Table 1 shows the composition of the EML in the device, while the device results and data are summarized in Table 2 and Table 3. As used herein, NPD, compound H, SD, and AlQ₃have the following structures:

TABLE 1 Compounds of EML in the devices Example Emitter Device Compound 28 Example 1 Device Compound 80 Example 2 Device Compound 81 Example 3 Device Compound 84 Example 4 Comparative Comparative example 1 compound 1 Comparative Comparative example 2 compound 2 Comparative Comparative example 3 compound 3

TABLE 2 Device results of Device examples 1 and comparative device example 1. LE at λ 1,000 1931 CIE max FWHM nits x y [nm] [nm] [cd/A] Device 0.66 0.34 620 52 26.2 Example 1 Comparative 0.65 0.35 620 55 25.7 example 1 Comparative 0.65 0.35 622 61 21.8 example 2

TABLE 3 Device results of Device examples 2-4 and comparative device example 3 LE at λ 1,000 1931 CIE max FWHM nits x y [nm] [nm] [cd/A] Device 0.66 0.34 621 55 23.0 Example 2 Device 0.66 0.34 622 54 20.9 Example 3 Device 0.65 0.35 622 52 19.7 Example 4 Comparative 0.66 0.34 625 56 19.0 example 3

Tables 2 and 3 summarize the performance of the devices. The 1931 CIE values were measured at 10 mA/cm². The luminous efficiency was measured at 1000 cd/m². The device examples have a full width at half maximum (FWHM) that is narrower than the comparative examples. In addition, the devices with inventive compounds have higher luminous efficiency than the devices with comparative compounds. When compared against devices using comparative compounds 1 and 2 as emitter, device with inventive compound 28 as emitter showed narrow FWHM (52 nm vs. 55 nm and 61 nm) and higher efficiency. (26.2 cd/A vs. 25.7 cd/A and 21.8 cd/A). Device examples 2, 3, and 4 also show superior characteristics compared to comparative example 3.

It is understood that the various embodiments described herein are by way of example only, and are not intended to limit the scope of the invention. For example, many of the materials and structures described herein may be substituted with other materials and structures without deviating from the spirit of the invention. The present invention as claimed may therefore include variations from the particular examples and preferred embodiments described herein, as will be apparent to one of skill in the art. It is understood that various theories as to why the invention works are not intended to be limiting.

Claims

1. A compound having a formula M(LA)x(LB)y:

wherein the ligand LA is

wherein the ligand LB is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein x+y is the oxidation state of the metal M;

wherein R1, R2, R3, and R4 are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein at least one of R1, R2, R3, and R4 has at least two C atoms;

wherein R5 is selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein RA represents mono, di, tri, or tetra substitution, or no substitution;

wherein RB represents mono, di, tri, tetra, penta, or hexa substitution;

wherein at least one RB has the following structure:

wherein each of RA and RB are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any adjacent substitutents of RA and RB are optionally joined to form a ring;

wherein R6, R7, and R8 are independently selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof; and

wherein at least one of R6, R7, and R8 is not hydrogen or deuterium.

2. The compound of claim 1, wherein M is selected from the group consisting of Ir, Rh, Re, Ru, Os, Pt, Au, and Cu.

3. The compound of claim 1, wherein M is Ir.

4. The compound of claim 1, wherein R5 is selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, and combinations thereof.

5. The compound of claim 1, wherein R5 is hydrogen.

6. The compound of claim 1, wherein R1, R2, R3, and R4 are alkyl or cycloalkyl.

7. The compound of claim 1, wherein R1, R2, R3, and R4 are independently selected from the group consisting of methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully deuterated variants thereof, and combinations thereof.

8. The compound of claim 1, wherein R6, R7, and R8 are independently selected from the group consisting of hydrogen, deuterium, methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully fluorinated variants thereof, fluorine, and combinations thereof.

9. The compound of claim 1, wherein RB is mono substitution.

10. The compound of claim 1, wherein the compound has the following formula: wherein n is 1 or 2.

11. The compound of claim 10, wherein n is 2.

12. The compound of claim 10, wherein RA is selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof.

13. The compound of claim 10, wherein the compound has the following formula:

wherein R9, and R10 are independently selected from the group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof.

14. The compound of claim 1, wherein LA is selected from the group consisting of LA1 to LA104 listed below:

LA1 through LA13, each represented by the formula

wherein in LA1, R7═CH3, and R6═R8═H;

in LA2, R7=isopropyl, and R6═R8═H;

in LA3, R7=isobutyl, and R6═R8═H;

in LA4, R7=cyclopentyl, and R6═R8═H;

in LA5, R7=neopentyl, and R6═R8═H;

in LA6, R7═F, and R6═R8═H;

in LA7, R7═H, and R6═R8═CH3;

in LA8, R7═H, and R6═R8=isopropyl;

in LA9, R7═H, and R6═R8=isobutyl;

in LA10, R7═H, and R6═R8=cyclopentyl;

in LA11, R7═H, and R6═R8=neopentyl;

in LA12, R7═H, and R6═R8═F, and

in LA13, R6═R7═R8═CH3;

LA14 through LA26, each represented by the formula

wherein in LA14, R7═CH3, and R6═R8═H;

in LA15, R7=isopropyl, and R6═R8═H;

in LA16, R7=isobutyl, and R6═R8═H;

in LA17, R7=cyclopentyl, and R6═R8═H;

in LA18, R7=neopentyl, and R6═R8═H;

in LA19, R7═F, and R6═R8═H;

in LA20, R7═H, and R6═R8═CH3;

in LA21, R7═H, and R6═R8=isopropyl;

in LA22, R7═H, and R6═R8=isobutyl;

in LA23, R7═H, and R6═R8=cyclopentyl;

in LA24, R7═H, and R6═R8=neopentyl;

in LA25, R7═H, and R6═R8═F; and

in LA26, R6═R7═R8═CH3;

LA27 through LA39, each represented by the formula

wherein in LA27, R7═CH3, and R6═R8═H;

in LA28, R7=isopropyl, and R6═R8═H;

in LA29, R7=isobutyl, and R6═R8═H;

in LA30, R7=cyclopentyl, and R6═R8═H;

in LA31, R7=neopentyl, and R6═R8═H;

in LA32, R7═F, and R6═R8═H;

in LA33, R7═H, and R6═R8═CH3;

in LA34, R7═H, and R6═R8=isopropyl;

in LA35, R7═H, and R6═R8=isobutyl;

in LA36, R7═H, and R6═R8=cyclopentyl;

in LA37, R7═H, and R6═R8=neopentyl;

in LA38, R7═H, and R6═R8═F; and

in LA39, R6═R7═R8═CH3;

LA40 through LA52, each represented by the formula

wherein in LA40, R7═CH3, and R6═R8═H;

in LA41, R7=isopropyl, and R6═R8═H;

in LA42, R7=isobutyl, and R6═R8═H;

in LA43, R7=cyclopentyl, and R6═R8═H;

in LA44, R7=neopentyl, and R6═R8═H;

in LA45, R7═F, and R6═R8═H;

in LA46, R7═H, and R6═R8═CH3;

in LA47, R7═H, and R6═R8=isopropyl;

in LA48, R7═H, and R6═R8=isobutyl;

in LA49, R7═H, and R6═R8=cyclopentyl;

in LA50, R7═H, and R6═R8=neopentyl;

in LA51, R7═H, and R6═R8═F; and

in LA52, R6═R7═R8═CH3;

LA53 through LA65, each represented by the formula

wherein in LA53, R7═CH3, and R6═R8═H;

in LA54, R7=isopropyl, and R6═R8═H;

in LA55, R7=isobutyl, and R6═R8═H;

in LA56, R7=cyclopentyl, and R6═R8═H;

in LA57, R7=neopentyl, and R6═R8═H;

in LA58, R7═F, and R6═R8═H;

in LA59, R7═H, and R6═R8═CH3;

in LA60, R7═H, and R6═R8=isopropyl;

in LA61, R7═H, and R6═R8=isobutyl;

in LA62, R7═H, and R6═R8=cyclopentyl;

in LA63, R7═H, and R6═R8=neopenty;

in LA64, R7═H, and R6═R8═F; and

in LA65, R6═R7═R8═CH3;

LA66 through LA78, each represented by the formula

wherein in LA66, R7═CH3, and R6═R8═H;

in LA67, R7=isopropyl, and R6═R8═H;

in LA68, R7=isobutyl, and R6═R8═H;

in LA69, R7=cyclopentyl, and R6═R8═H;

in LA70, R7=neopentyl, and R6═R8═H;

in LA71, R7═F, and R6═R8═H;

in LA72, R7═H, and R6═R8═CH3;

in LA73, R7═H, and R6═R8=isopropyl;

in LA74, R7═H, and R6═R8=isobutyl;

in LA75, R7═H, and R6═R8=cyclopentyl;

in LA76, R7═H, and R6═R8=neopentyl;

in LA77, R7═H, and R6═R8═F; and

in LA78, R6═R7═R8═CH3;

LA79 through LA91, each represented by the formula

wherein in LA79, R7═CH3, and R6═R8═H;

in LA80, R7=isopropyl, and R6═R8═H;

in LA81, R7=isobutyl, and R6═R8═H;

in LA82, R7=cyclopentyl, and R6═R8═H;

in LA83, R7=neopentyl, and R6═R8═H;

in LA84, R7═F, and R6═R8═H;

in LA85, R7═H, and R6═R8═CH3;

in LA86, R7═H, and R6═R8=isopropyl;

in LA87, R7═H, and R6═R8=isobutyl;

in LA88, R7═H, and R6═R8=cyclopentyl;

in LA89, R7═H, and R6═R8=neopentyl;

in LA90, R7═H, and R6═R8═F; and

in LA91, R6═R7═R8═CH3; and

LA92 through LA104, each represented by the formula

wherein in LA92, R7═CH3, and R6═R8═H;

in LA93, R7=isopropyl, and R6═R8═H;

in LA94, R7=isobutyl, and R6═R8═H;

in LA95, R7=cyclopentyl, and R6═R8═H;

in LA96, R7=neopentyl, and R6═R8═H;

in LA97, R7═F, and R6═R8═H;

in LA98, R7═H, and R6═R8═CH3;

in LA99, R7═H, and R6═R8=isopropyl;

in LA100, R7═H, and R6═R8=isobutyl;

in LA101, R7═H, and R6═R8=cyclopentyl;

in LA102, R7═H, and R6═R8=neopentyl;

in LA103, R7═H, and R6═R8═F; and

in LA104, R6═R7═R8═CH3.

15. The compound of claim 1, wherein LB is selected from the group consisting of LB1-LB9 listed below:

16. The compound of claim 15, wherein LB is selected from the group consisting of LB1-LB9 listed below: Compound Number LA LB 1 LA1 LB1 2 LA2 LB1 3 LA3 LB1 4 LA4 LB1 5 LA5 LB1 6 LA6 LB1 7 LA7 LB1 8 LA8 LB1 9 LA9 LB1 10 LA10 LB1 11 LA11 LB1 12 LA12 LB1 13 LA13 LB1 14 LA14 LB1 15 LA15 LB1 16 LA16 LB1 17 LA17 LB1 18 LA18 LB1 19 LA19 LB1 20 LA20 LB1 21 LA21 LB1 22 LA22 LB1 23 LA23 LB1 24 LA24 LB1 25 LA25 LB1 26 LA26 LB1 27 LA27 LB1 28 LA28 LB1 29 LA29 LB1 30 LA30 LB1 31 LA31 LB1 32 LA32 LB1 33 LA33 LB1 34 LA34 LB1 35 LA35 LB1 36 LA36 LB1 37 LA37 LB1 38 LA38 LB1 39 LA39 LB1 40 LA40 LB1 41 LA41 LB1 42 LA42 LB1 43 LA43 LB1 44 LA44 LB1 45 LA45 LB1 46 LA46 LB1 47 LA47 LB1 48 LA48 LB1 49 LA49 LB1 50 LA50 LB1 51 LA51 LB1 52 LA52 LB1 53 LA53 LB1 54 LA54 LB1 55 LA55 LB1 56 LA56 LB1 57 LA57 LB1 58 LA58 LB1 59 LA59 LB1 60 LA60 LB1 61 LA61 LB1 62 LA62 LB1 63 LA63 LB1 64 LA64 LB1 65 LA65 LB1 66 LA66 LB1 67 LA67 LB1 68 LA68 LB1 69 LA69 LB1 70 LA70 LB1 71 LA71 LB1 72 LA72 LB1 73 LA73 LB1 74 LA74 LB1 75 LA75 LB1 76 LA76 LB1 77 LA77 LB1 78 LA78 LB1 79 LA79 LB1 80 LA80 LB1 81 LA81 LB1 82 LA82 LB1 83 LA83 LB1 84 LA84 LB1 85 LA85 LB1 86 LA86 LB1 87 LA87 LB1 88 LA88 LB1 89 LA89 LB1 90 LA90 LB1 91 LA91 LB1 92 LA92 LB1 93 LA93 LB1 94 LA94 LB1 95 LA95 LB1 96 LA96 LB1 97 LA97 LB1 98 LA98 LB1 99 LA99 LB1 100 LA100 LB1 101 LA101 LB1 102 LA102 LB1 103 LA103 LB1 104 LA104 LB1 105 LA1 LB2 106 LA2 LB2 107 LA3 LB2 108 LA4 LB2 109 LA5 LB2 110 LA6 LB2 111 LA7 LB2 112 LA8 LB2 113 LA9 LB2 114 LA10 LB2 115 LA11 LB2 116 LA12 LB2 117 LA13 LB2 118 LA14 LB2 119 LA15 LB2 120 LA16 LB2 121 LA17 LB2 122 LA18 LB2 123 LA19 LB2 124 LA20 LB2 125 LA21 LB2 126 LA22 LB2 127 LA23 LB2 128 LA24 LB2 129 LA25 LB2 130 LA26 LB2 131 LA27 LB2 132 LA28 LB2 133 LA29 LB2 134 LA30 LB2 135 LA31 LB2 136 LA32 LB2 137 LA33 LB2 138 LA34 LB2 139 LA35 LB2 140 LA36 LB2 141 LA37 LB2 142 LA38 LB2 143 LA39 LB2 144 LA40 LB2 145 LA41 LB2 146 LA42 LB2 147 LA43 LB2 148 LA44 LB2 149 LA45 LB2 150 LA46 LB2 151 LA47 LB2 152 LA48 LB2 153 LA49 LB2 154 LA50 LB2 155 LA51 LB2 156 LA52 LB2 157 LA53 LB2 158 LA54 LB2 159 LA55 LB2 160 LA56 LB2 161 LA57 LB2 162 LA58 LB2 163 LA59 LB2 164 LA60 LB2 165 LA61 LB2 166 LA62 LB2 167 LA63 LB2 168 LA64 LB2 169 LA65 LB2 170 LA66 LB2 171 LA67 LB2 172 LA68 LB2 173 LA69 LB2 174 LA70 LB2 175 LA71 LB2 176 LA72 LB2 177 LA73 LB2 178 LA74 LB2 179 LA75 LB2 180 LA76 LB2 181 LA77 LB2 182 LA78 LB2 183 LA79 LB2 184 LA80 LB2 185 LA81 LB2 186 LA82 LB2 187 LA83 LB2 188 LA84 LB2 189 LA85 LB2 190 LA86 LB2 191 LA87 LB2 192 LA88 LB2 193 LA89 LB2 194 LA90 LB2 195 LA91 LB2 196 LA92 LB2 197 LA93 LB2 198 LA94 LB2 199 LA95 LB2 200 LA96 LB2 201 LA97 LB2 202 LA98 LB2 203 LA99 LB2 204 LA100 LB2 205 LA101 LB2 206 LA102 LB2 207 LA103 LB2 208 LA104 LB2 209 LA1 LB3 210 LA2 LB3 211 LA3 LB3 212 LA4 LB3 213 LA5 LB3 214 LA6 LB3 215 LA7 LB3 216 LA8 LB3 217 LA9 LB3 218 LA10 LB3 219 LA11 LB3 220 LA12 LB3 221 LA13 LB3 222 LA14 LB3 223 LA15 LB3 224 LA16 LB3 225 LA17 LB3 226 LA18 LB3 227 LA19 LB3 228 LA20 LB3 229 LA21 LB3 230 LA22 LB3 231 LA23 LB3 232 LA24 LB3 233 LA25 LB3 234 LA26 LB3 235 LA27 LB3 236 LA28 LB3 237 LA29 LB3 238 LA30 LB3 239 LA31 LB3 240 LA32 LB3 241 LA33 LB3 242 LA34 LB3 243 LA35 LB3 244 LA36 LB3 245 LA37 LB3 246 LA38 LB3 247 LA39 LB3 248 LA40 LB3 249 LA41 LB3 250 LA42 LB3 251 LA43 LB3 252 LA44 LB3 253 LA45 LB3 254 LA46 LB3 255 LA47 LB3 256 LA48 LB3 257 LA49 LB3 258 LA50 LB3 259 LA51 LB3 260 LA52 LB3 261 LA53 LB3 262 LA54 LB3 263 LA55 LB3 264 LA56 LB3 265 LA57 LB3 266 LA58 LB3 267 LA59 LB3 268 LA60 LB3 269 LA61 LB3 270 LA62 LB3 271 LA63 LB3 272 LA64 LB3 273 LA65 LB3 274 LA66 LB3 275 LA67 LB3 276 LA68 LB3 277 LA69 LB3 278 LA70 LB3 279 LA71 LB3 280 LA72 LB3 281 LA73 LB3 282 LA74 LB3 283 LA75 LB3 284 LA76 LB3 285 LA77 LB3 286 LA78 LB3 287 LA79 LB3 288 LA80 LB3 289 LA81 LB3 290 LA82 LB3 291 LA83 LB3 292 LA84 LB3 293 LA85 LB3 294 LA86 LB3 295 LA87 LB3 296 LA88 LB3 297 LA89 LB3 298 LA90 LB3 299 LA91 LB3 300 LA92 LB3 301 LA93 LB3 302 LA94 LB3 303 LA95 LB3 304 LA96 LB3 305 LA97 LB3 306 LA98 LB3 307 LA99 LB3 308 LA100 LB3 309 LA101 LB3 310 LA102 LB3 311 LA103 LB3 312 LA104 LB3 313 LA1 LB4 314 LA2 LB4 315 LA3 LB4 316 LA4 LB4 317 LA5 LB4 318 LA6 LB4 319 LA7 LB4 320 LA8 LB4 321 LA9 LB4 322 LA10 LB4 323 LA11 LB4 324 LA12 LB4 325 LA13 LB4 326 LA14 LB4 327 LA15 LB4 328 LA16 LB4 329 LA17 LB4 330 LA18 LB4 331 LA19 LB4 332 LA20 LB4 333 LA21 LB4 334 LA22 LB4 335 LA23 LB4 336 LA24 LB4 337 LA25 LB4 338 LA26 LB4 339 LA27 LB4 340 LA28 LB4 341 LA29 LB4 342 LA30 LB4 343 LA31 LB4 344 LA32 LB4 345 LA33 LB4 346 LA34 LB4 347 LA35 LB4 348 LA36 LB4 349 LA37 LB4 350 LA38 LB4 351 LA39 LB4 352 LA40 LB4 353 LA41 LB4 354 LA42 LB4 355 LA43 LB4 356 LA44 LB4 357 LA45 LB4 358 LA46 LB4 359 LA47 LB4 360 LA48 LB4 361 LA49 LB4 362 LA50 LB4 363 LA51 LB4 364 LA52 LB4 365 LA53 LB4 366 LA54 LB4 367 LA55 LB4 368 LA56 LB4 369 LA57 LB4 370 LA58 LB4 371 LA59 LB4 372 LA60 LB4 373 LA61 LB4 374 LA62 LB4 375 LA63 LB4 376 LA64 LB4 377 LA65 LB4 378 LA66 LB4 379 LA67 LB4 380 LA68 LB4 381 LA69 LB4 382 LA70 LB4 383 LA71 LB4 384 LA72 LB4 385 LA73 LB4 386 LA74 LB4 387 LA75 LB4 388 LA76 LB4 389 LA77 LB4 390 LA78 LB4 391 LA79 LB4 392 LA80 LB4 393 LA81 LB4 394 LA82 LB4 395 LA83 LB4 396 LA84 LB4 397 LA85 LB4 398 LA86 LB4 399 LA87 LB4 400 LA88 LB4 401 LA89 LB4 402 LA90 LB4 403 LA91 LB4 404 LA92 LB4 405 LA93 LB4 406 LA94 LB4 407 LA95 LB4 408 LA96 LB4 409 LA97 LB4 410 LA98 LB4 411 LA99 LB4 412 LA100 LB4 413 LA101 LB4 414 LA102 LB4 415 LA103 LB4 416 LA104 LB4 417 LA1 LB5 418 LA2 LB5 419 LA3 LB5 420 LA4 LB5 421 LA5 LB5 422 LA6 LB5 423 LA7 LB5 424 LA8 LB5 425 LA9 LB5 426 LA10 LB5 427 LA11 LB5 428 LA12 LB5 429 LA13 LB5 430 LA14 LB5 431 LA15 LB5 432 LA16 LB5 433 LA17 LB5 434 LA18 LB5 435 LA19 LB5 436 LA20 LB5 437 LA21 LB5 438 LA22 LB5 439 LA23 LB5 440 LA24 LB5 441 LA25 LB5 442 LA26 LB5 443 LA27 LB5 444 LA28 LB5 445 LA29 LB5 446 LA30 LB5 447 LA31 LB5 448 LA32 LB5 449 LA33 LB5 450 LA34 LB5 451 LA35 LB5 452 LA36 LB5 453 LA37 LB5 454 LA38 LB5 455 LA39 LB5 456 LA40 LB5 457 LA41 LB5 458 LA42 LB5 459 LA43 LB5 460 LA44 LB5 461 LA45 LB5 462 LA46 LB5 463 LA47 LB5 464 LA48 LB5 465 LA49 LB5 466 LA50 LB5 467 LA51 LB5 468 LA52 LB5 469 LA53 LB5 470 LA54 LB5 471 LA55 LB5 472 LA56 LB5 473 LA57 LB5 474 LA58 LB5 475 LA59 LB5 476 LA60 LB5 477 LA61 LB5 478 LA62 LB5 479 LA63 LB5 480 LA64 LB5 481 LA65 LB5 482 LA66 LB5 483 LA67 LB5 484 LA68 LB5 485 LA69 LB5 486 LA70 LB5 487 LA71 LB5 488 LA72 LB5 489 LA73 LB5 490 LA74 LB5 491 LA75 LB5 492 LA76 LB5 493 LA77 LB5 494 LA78 LB5 495 LA79 LB5 496 LA80 LB5 497 LA81 LB5 498 LA82 LB5 499 LA83 LB5 500 LA84 LB5 501 LA85 LB5 502 LA86 LB5 503 LA87 LB5 504 LA88 LB5 505 LA89 LB5 506 LA90 LB5 507 LA91 LB5 508 LA92 LB5 509 LA93 LB5 510 LA94 LB5 511 LA95 LB5 512 LA96 LB5 513 LA97 LB5 514 LA98 LB5 515 LA99 LB5 516 LA100 LB5 517 LA101 LB5 518 LA102 LB5 519 LA103 LB5 520 LA104 LB5 521 LA1 LB6 522 LA2 LB6 523 LA3 LB6 524 LA4 LB6 525 LA5 LB6 526 LA6 LB6 527 LA7 LB6 528 LA8 LB6 529 LA9 LB6 530 LA10 LB6 531 LA11 LB6 532 LA12 LB6 533 LA13 LB6 534 LA14 LB6 535 LA15 LB6 536 LA16 LB6 537 LA17 LB6 538 LA18 LB6 539 LA19 LB6 540 LA20 LB6 541 LA21 LB6 542 LA22 LB6 543 LA23 LB6 544 LA24 LB6 545 LA25 LB6 546 LA26 LB6 547 LA27 LB6 548 LA28 LB6 549 LA29 LB6 550 LA30 LB6 551 LA31 LB6 552 LA32 LB6 553 LA33 LB6 554 LA34 LB6 555 LA35 LB6 556 LA36 LB6 557 LA37 LB6 558 LA38 LB6 559 LA39 LB6 560 LA40 LB6 561 LA41 LB6 562 LA42 LB6 563 LA43 LB6 564 LA44 LB6 565 LA45 LB6 566 LA46 LB6 567 LA47 LB6 568 LA48 LB6 569 LA49 LB6 570 LA50 LB6 571 LA51 LB6 572 LA52 LB6 573 LA53 LB6 574 LA54 LB6 575 LA55 LB6 576 LA56 LB6 577 LA57 LB6 578 LA58 LB6 579 LA59 LB6 580 LA60 LB6 581 LA61 LB6 582 LA62 LB6 583 LA63 LB6 584 LA64 LB6 585 LA65 LB6 586 LA66 LB6 587 LA67 LB6 588 LA68 LB6 589 LA69 LB6 590 LA70 LB6 591 LA71 LB6 592 LA72 LB6 593 LA73 LB6 594 LA74 LB6 595 LA75 LB6 596 LA76 LB6 597 LA77 LB6 598 LA78 LB6 599 LA79 LB6 600 LA80 LB6 601 LA81 LB6 602 LA82 LB6 603 LA83 LB6 604 LA84 LB6 605 LA85 LB6 606 LA86 LB6 607 LA87 LB6 608 LA88 LB6 609 LA89 LB6 610 LA90 LB6 611 LA91 LB6 612 LA92 LB6 613 LA93 LB6 614 LA94 LB6 615 LA95 LB6 616 LA96 LB6 617 LA97 LB6 618 LA98 LB6 619 LA99 LB6 620 LA100 LB6 621 LA101 LB6 622 LA102 LB6 623 LA103 LB6 624 LA104 LB6 625 LA1 LB7 626 LA2 LB7 627 LA3 LB7 628 LA4 LB7 629 LA5 LB7 630 LA6 LB7 631 LA7 LB7 632 LA8 LB7 633 LA9 LB7 634 LA10 LB7 635 LA11 LB7 636 LA12 LB7 637 LA13 LB7 638 LA14 LB7 639 LA15 LB7 640 LA16 LB7 641 LA17 LB7 642 LA18 LB7 643 LA19 LB7 644 LA20 LB7 645 LA21 LB7 646 LA22 LB7 647 LA23 LB7 648 LA24 LB7 649 LA25 LB7 650 LA26 LB7 651 LA27 LB7 652 LA28 LB7 653 LA29 LB7 654 LA30 LB7 655 LA31 LB7 656 LA32 LB7 657 LA33 LB7 658 LA34 LB7 659 LA35 LB7 660 LA36 LB7 661 LA37 LB7 662 LA38 LB7 663 LA39 LB7 664 LA40 LB7 665 LA41 LB7 666 LA42 LB7 667 LA43 LB7 668 LA44 LB7 669 LA45 LB7 670 LA46 LB7 671 LA47 LB7 672 LA48 LB7 673 LA49 LB7 674 LA50 LB7 675 LA51 LB7 676 LA52 LB7 677 LA53 LB7 678 LA54 LB7 679 LA55 LB7 680 LA56 LB7 681 LA57 LB7 682 LA58 LB7 683 LA59 LB7 684 LA60 LB7 685 LA61 LB7 686 LA62 LB7 687 LA63 LB7 688 LA64 LB7 689 LA65 LB7 690 LA66 LB7 691 LA67 LB7 692 LA68 LB7 693 LA69 LB7 694 LA70 LB7 695 LA71 LB7 696 LA72 LB7 697 LA73 LB7 698 LA74 LB7 699 LA75 LB7 700 LA76 LB7 701 LA77 LB7 702 LA78 LB7 703 LA79 LB7 704 LA80 LB7 705 LA81 LB7 706 LA82 LB7 707 LA83 LB7 708 LA84 LB7 709 LA85 LB7 710 LA86 LB7 711 LA87 LB7 712 LA88 LB7 713 LA89 LB7 714 LA90 LB7 715 LA91 LB7 716 LA92 LB7 717 LA93 LB7 718 LA94 LB7 719 LA95 LB7 720 LA96 LB7 721 LA97 LB7 722 LA98 LB7 723 LA99 LB7 724 LA100 LB7 725 LA101 LB7 726 LA102 LB7 727 LA103 LB7 728 LA104 LB7 729 LA1 LB8 730 LA2 LB8 731 LA3 LB8 732 LA4 LB8 733 LA5 LB8 734 LA6 LB8 735 LA7 LB8 736 LA8 LB8 737 LA9 LB8 738 LA10 LB8 739 LA11 LB8 740 LA12 LB8 741 LA13 LB8 742 LA14 LB8 743 LA15 LB8 744 LA16 LB8 745 LA17 LB8 746 LA18 LB8 747 LA19 LB8 748 LA20 LB8 749 LA21 LB8 750 LA22 LB8 751 LA23 LB8 752 LA24 LB8 753 LA25 LB8 754 LA26 LB8 755 LA27 LB8 756 LA28 LB8 757 LA29 LB8 758 LA30 LB8 759 LA31 LB8 760 LA32 LB8 761 LA33 LB8 762 LA34 LB8 763 LA35 LB8 764 LA36 LB8 765 LA37 LB8 766 LA38 LB8 767 LA39 LB8 768 LA40 LB8 769 LA41 LB8 770 LA42 LB8 771 LA43 LB8 772 LA44 LB8 773 LA45 LB8 774 LA46 LB8 775 LA47 LB8 776 LA48 LB8 777 LA49 LB8 778 LA50 LB8 779 LA51 LB8 780 LA52 LB8 781 LA53 LB8 782 LA54 LB8 783 LA55 LB8 784 LA56 LB8 785 LA57 LB8 786 LA58 LB8 787 LA59 LB8 788 LA60 LB8 789 LA61 LB8 790 LA62 LB8 791 LA63 LB8 792 LA64 LB8 793 LA65 LB8 794 LA66 LB8 795 LA67 LB8 796 LA68 LB8 797 LA69 LB8 798 LA70 LB8 799 LA71 LB8 800 LA72 LB8 801 LA73 LB8 802 LA74 LB8 803 LA75 LB8 804 LA76 LB8 805 LA77 LB8 806 LA78 LB8 807 LA79 LB8 808 LA80 LB8 809 LA81 LB8 810 LA82 LB8 811 LA83 LB8 812 LA84 LB8 813 LA85 LB8 814 LA86 LB8 815 LA87 LB8 816 LA88 LB8 817 LA89 LB8 818 LA90 LB8 819 LA91 LB8 820 LA92 LB8 821 LA93 LB8 822 LA94 LB8 823 LA95 LB8 824 LA96 LB8 825 LA97 LB8 826 LA98 LB8 827 LA99 LB8 828 LA100 LB8 829 LA101 LB8 830 LA102 LB8 831 LA103 LB8 832 LA104 LB8 833 LA1 LB9 834 LA2 LB9 835 LA3 LB9 836 LA4 LB9 837 LA5 LB9 838 LA6 LB9 839 LA7 LB9 840 LA8 LB9 841 LA9 LB9 842 LA10 LB9 843 LA11 LB9 844 LA12 LB9 845 LA13 LB9 846 LA14 LB9 847 LA15 LB9 848 LA16 LB9 849 LA17 LB9 850 LA18 LB9 851 LA19 LB9 852 LA20 LB9 853 LA21 LB9 854 LA22 LB9 855 LA23 LB9 856 LA24 LB9 857 LA25 LB9 858 LA26 LB9 859 LA27 LB9 860 LA28 LB9 861 LA29 LB9 862 LA30 LB9 863 LA31 LB9 864 LA32 LB9 865 LA33 LB9 866 LA34 LB9 867 LA35 LB9 868 LA36 LB9 869 LA37 LB9 870 LA38 LB9 871 LA39 LB9 872 LA40 LB9 873 LA41 LB9 874 LA42 LB9 875 LA43 LB9 876 LA44 LB9 877 LA45 LB9 878 LA46 LB9 879 LA47 LB9 880 LA48 LB9 881 LA49 LB9 882 LA50 LB9 883 LA51 LB9 884 LA52 LB9 885 LA53 LB9 886 LA54 LB9 887 LA55 LB9 888 LA56 LB9 889 LA57 LB9 890 LA58 LB9 891 LA59 LB9 892 LA60 LB9 893 LA61 LB9 894 LA62 LB9 895 LA63 LB9 896 LA64 LB9 897 LA65 LB9 898 LA66 LB9 899 LA67 LB9 900 LA68 LB9 901 LA69 LB9 902 LA70 LB9 903 LA71 LB9 904 LA72 LB9 905 LA73 LB9 906 LA74 LB9 907 LA75 LB9 908 LA76 LB9 909 LA77 LB9 910 LA78 LB9 911 LA79 LB9 912 LA80 LB9 913 LA81 LB9 914 LA82 LB9 915 LA83 LB9 916 LA84 LB9 917 LA85 LB9 918 LA86 LB9 919 LA87 LB9 920 LA88 LB9 921 LA89 LB9 922 LA90 LB9 923 LA91 LB9 924 LA92 LB9 925 LA93 LB9 926 LA94 LB9 927 LA95 LB9 928 LA96 LB9 929 LA97 LB9 930 LA98 LB9 931 LA99 LB9 932 LA100 LB9 933 LA101 LB9 934 LA102 LB9 935 LA103 LB9 936 LA104 LB9.

wherein the compound comprises ligand LA and ligand LB selected from the group consisting of:

17. The compound of claim 1, wherein the compound is selected from the group consisting of

18. A first device comprising a first organic light emitting device, the first organic light emitting device comprising:

an anode;

a cathode; and

an organic layer, disposed between the anode and the cathode, comprising a compound having a formula M(LA)x(LB)y:

wherein the ligand LA is

wherein the ligand LB is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein x+y is the oxidation state of the metal M;

wherein R1, R2, R3, and R4 are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein at least one of R1, R2, R3, and R4 has at least two C atoms;

wherein R5 is selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein RA represents mono, di, tri, or tetra substitution, or no substitution;

wherein RB represents mono, di, tri, tetra, penta, or hexa substitution;

wherein at least one RB has the following structure:

wherein each of RA and RB are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any adjacent substitutents of RA and RB are optionally joined to form a ring;

wherein R6, R7, and R8 are independently selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof; and

wherein at least one of R6, R7, and R8 is not hydrogen or deuterium.

19. A formulation comprising a compound having a formula M(LA)x(LB)y:

wherein the ligand LA is

wherein the ligand LB is

wherein M is a metal having an atomic number greater than 40;

wherein x is 1, or 2;

wherein y is 1, or 2;

wherein x+y is the oxidation state of the metal M;

wherein R1, R2, R3, and R4 are independently selected from group consisting of alkyl, cycloalkyl, aryl, and heteroaryl;

wherein at least one of R1, R2, R3, and R4 has at least two C atoms;

wherein R5 is selected from group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein RA represents mono, di, tri, or tetra substitution, or no substitution;

wherein RB represents mono, di, tri, tetra, penta, or hexa substitution;

wherein at least one RB has the following structure:

wherein each of RA and RB are independently selected from the group consisting of hydrogen, deuterium, halide, alkyl, cycloalkyl, heteroalkyl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carbonyl, carboxylic acids, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof;

wherein any adjacent substitutents of RA and RB are optionally joined to form a ring;

wherein R6, R7, and R8 are independently selected from group consisting of hydrogen, deuterium, alkyl, cycloalkyl, halide, and combinations thereof; and

wherein at least one of R6, R7, and R8 is not hydrogen or deuterium.

20. The compound of claim 1, wherein R1 is cycloalkyl.

21. The compound of claim 1, wherein R1, R2, R3, and R4 are independently selected from the group consisting of ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl, 2,2-dimethylpropyl, cyclobutyl, cyclopentyl, cyclohexyl, partially or fully deuterated variants thereof, and combinations thereof.